Analyzing Every Potential Starting Pitcher Innings Limit for 2021

Alexander Chase examines which pitchers might face innings limits

It’s that time of year again.

The COVID-shortened season means that there’s not a natural way to estimate how many innings a pitcher might be able to throw. Almost every player will be doubling their innings from last year. The obvious outcome of this was that every starting pitcher was a risk for an innings limit going into the season.

The other outcome, at least so far, has been a record number of injuries. Teams have had to scratch their plans for six-man rotations because they haven’t had five (or oven four) major-league quality arms to use. Some starters have been thrust into full-size workloads ahead of schedule (hello, Brandon Woodruff!) while others have just been hurt too much to possibly rack up career-highs in innings pitched.

We should see innings limits for what they are: a tradeoff of risk from one player to another. When the Nationals placed a 160 inning cap on Stephen Strasburg in 2012, someone else still had to pitch those innings. The Nationals didn’t just see the potential risk of losing him in the future as being greater than how much he was worth that year: they had to weigh that decision against the increased chance of injury for the other pitchers who were filling in for him. For teams with the depth to make those choices, it’s easy to limit rookies. For those that don’t — especially those in playoff races who can’t risk losing their ace for the stretch run — it’s no easy choice. I’m okay with throwing my hands in the air about those situations to a degree. The reality is that we’ll know more when we know more.

Our task is simplified because the CBA incentivizes teams to cap innings at the beginning of the year, not the end. By holding players down in the minors before the AA or AAA season starts, teams can eat away at the number of service time days they will accrue, reduce the chance that they’ll pick up a season of service time while being on the IL, and potentially have them available with gas in the tank for the playoffs. There are a handful of rookies who fall into that category this year, and we should expect that to be the case until the CBA isn’t written to exploit minor leaguers.

The other reality is that rosters staying at 26 players means that not everyone can be limited. As a result, we have to choose who to place some faith in. So, for the purposes of this exercise, I’m choosing to exclude most starting pitchers who have thrown 150 innings in a single professional season in the last three years. There are reasonable exceptions — anyone who’s had Tommy John surgery since 2018 is likely to need some regular maintenance rest — but I can’t reasonably expect Zack Wheeler or to be limited even if he’s on pace to potentially triple his number of innings from last year. There are nine innings almost every day, somebody has to throw them, and his experience being built up to throw a full season in the past is the best evidence I can that his team trusts him to do it again.

I also came in expecting to exclude most players who aren’t on pace to pass that 150 inning mark. Most pitchers who haven’t yet pitched enough innings to be on that pace have already had their seasons shortened by injuries or other factors, but the list of those on pace to fall short of that mark who still deserved a look was larger than I initially thought.

Finally, I’m limiting players under consideration just to those who have shown themselves to be good enough to hold onto if they’re having starts skipped. This ended up not mattering much — those sorts of players are mostly innings-eaters who have already hit 150 before in their career.

With that in mind, I’m separating the remaining players into three groups of very unequal size:

  • Already Limited is for the players who are already seeing their outings shortened or skipped entirely. This is self-explanatory.
  • High Risk is for the starters that I believe could either miss more than two starts. We have details of some sort for most of these players about innings targets from their teams. In normal years, these would be most of the players we’d be examining in a piece like this.
  • Low Risk is mostly starters who have been in the league for several years but who haven’t yet thrown 150 innings, but I’m also grouping in some rookies who look to be on track for reasonable targets. They could all receive a skipped start or so when it’s convenient for a team, but we should expect them to be treated normally for the rest of the year.

Let’s get to this.


Already Limited

Trevor Rogers (Miami Marlins)

2021: 110 IP (Pace: ~160 IP) / 2020: 28 IP / 2019: 136.2 IP

The Marlins previously told reporters that Trevor Rogers was slated for up to 175 innings this year and that after getting extra rest around the All-Star break, he wasn’t anticipated to miss any more starts. In the month since that report, however, Rogers has yet to throw six innings in a game (his last quality start was June 15) and he’s seen his pitch counts dwindle. His most recent start against the Yankees went 74 pitches — one less than a curiously round number — and he was pulled with two outs in the fourth. Even if Rogers does make the rest of his starts, it looks like his leash is now shorter by design. With the Marlins out of the playoff picture, there’s no reason to expect Rogers to reach 170 innings. Even using his season-long IPS for pace seems wrong new: the more likely case is that he’s below 160.


Freddy Peralta (Milwaukee Brewers)

2021: 108 IP (Pace: ~160 IP) / 2020: 29.1 IP / 2019: 85 IP

I suppose this is what happens when a converted reliever moves to the rotation, but the equation is different for Freddy Peralta because he’s been converted into an All-Star starter for a team that’s leading its division because of its pitching. Peralta was given extended rest coming out of the All-Star break, but he is still set to blow past anything close to what he’s done before. He’s been less limited than others in this section, but it would not be surprising to see him have starts skipped or cut short toward the end of the season if the Brewers have a cushion in the NL Central.


Casey Mize (Detroit Tigers)

2021: 111 IP (Pace: ~150 IP) / 2020: 28.1 IP  / 2019: 78.2 IP 

Detroit unveiled a plan in early. July to limit Casey Mize’s rest-of-season innings on a start-by-start basis rather than by shutting him down. They’ve only deviated from it only once, in his most recent start, which was an 88-pitch seven-inning gem the day after almost everyone in the Tigers bullpen pitched in a 17–14 win over the Twins. Don’t expect that to be the norm. Mize might have a limited impact on baseball for the rest of the year, but the long-term impact of the Tigers’ plan for him will likely reverberate throughout the league for years. If it’s successful, we should expect it to be the answer to the Nationals’ shutdown of Stephen Strasburg. If anything, his ability to pitch well over seven innings after not doing so for a month suggests it might.


High Risk

Julio Urías (Los Angeles Dodgers)

2021: 129.2 IP (Pace: ~ 180 IP) / 2020: 55 IP / 2019: 81.2 IP

During spring training, Dodgers pitching coach Mark Prior hinted that Julio Urías might have some restrictions this year, saying “We can’t just turn him loose and say, ‘Here, try to go out and make 30 starts and 200 innings.’ I think that would be reckless in some respects.” If we’re translating that to an innings target of around 180 frames, Urías is roughly on target to reach that by the end of the regular season. The reality for the Dodgers, though, is that they’ll need Urías to throw at every opportunity for the rest of the year just to finish 162 games. If they have enough healthy arms, they might find some chances to limit him, but that’s a big if with Clayton Kershaw, Tony Gonsolin, and Danny Duffy all on the shelf at the moment.


Carlos Rodón (Chicago White Sox)

2021: 104.2 IP (Pace: ~ 160 IP) / 2020: 7.2 IP / 2019: 34.2 IP

The oft-injured Carlos Rodón was exactly the sort of reclamation project that first-year White Sox pitching coach Ethan Katz built his reputation around fixing. During spring training, Katz discussed a tailor-made plan just to keep Rodón healthy that’s clearly been working, but he also hinted at potential innings limits. With the White Sox on course to win their division with weeks to go in the regular season, there may be ample opportunity to give Rodón some extra rest before what they hope will be a long playoff run. The line between an inning limit and extra playoff rest is murky, but it’s clear that it would be easy for Rodón to pitch much less in the last two weeks of the regular season.


Tarik Skubal (Detroit Tigers)

[2021: 105.1 IP (Pace: ~ 155 IP) / 2020: 32 IP / 2019: 122.2 IP

A.J. Hinch has said that he doesn’t plan to limit both Mize and Tarik Skubal at the same time. Between Skubal’s record of pitching more innings in the minors, the time he spent in the bullpen early in the year, and the practical reality of how difficult a soft bullpen day every three days would be, Hinch’s comments are no surprise. Skubal’s nascent home run problem might be a larger threat to his innings than anything else right now, but he deserves to be monitored closely as the season runs its course. It’s possible that this workload could be related to his recent dip in form, and if that’s the case, some time off wouldn’t be that surprising.


Luis Garcia (Houston Astros)

2021: 100.2 IP (Pace: ~ 150 IP) / 2020: 12.1 IP / 2019: 108.2 IP

No team will be better positioned to give their starters extra rest during the stretch run than the Houston Astros, who currently boast seven potential starters capable of pitching at or above an MLB average level, a newly-refreshed bullpen, and the MLB’s best offense. It would be no surprise to see Luis Garcia in particular see some extra rest, time in the bullpen, or some combination of the two as a result. It’s unlikely that Cristian Javier takes back his starting spot, but with José Urquidy eventually returning from the IL, Garcia is probably the pitcher on this list that their club would most easily be able to limit. He’s also the young pitcher they might most want to protect: Garcia trails only Oakland’s Cole Irvin in WAR among AL rookies at the moment, so even if Jake Odorizzi might not make the playoff rotation, bumping Garcia for him might be best for the team in the long-run.


Adbert Alzolay (Chicago Cubs)

 2021: 98.1 IP (Pace: 145 IP) / 2020: 21.1 IP / 2019: 86.2 IP

As of late May, Chicago had no plans to limit Adbert Alzolay’s innings. Cubs pitching coach Tommy Hottovy remarked then, when he was putting the bow on a month with a 3.14 ERA, that they would take a “fluid” approach and make decisions on Alzolay’s health later in the year. Alzolay hasn’t been quite the same in the two months since, putting up a near-seven ERA in June before rebounding somewhat in July. With the Cubs selling off nearly everything at the deadline, the incentives have also changed. It would make sense for Chicago to put the brakes on the promising young pitcher’s season eventually. Whether that looks like a Mize plan or just an early end to his year remains to be seen, but either way, 145 innings seems unlikely for him.


Low Risk

Brandon Woodruff (Milwaukee Brewers)

2021: 131.1 IP (Pace: ~185 IP) / 2020: 73.2 IP / 2019: 121.2 IP

We have no news about an impending shutdown for Brandon Woodruff, and the Brewers essentially need him to be incredible through the end of October anyway. Should their margin in the NL Central widen, though, it’s probable that he’ll sit (or at least be pulled early) during the last week or so of the season. We would have expected Woodruff to top 200 innings this year if not for the COVID-shortened 2020 season, so the fact that he’ll likely top 180 isn’t that surprising.


Frankie Montas (Oakland Athletics)

2021: 119 IP (Pace: ~170 IP) / 2020: 53 IP / 2019: 96 IP 

Frankie Montas has battled injuries over the past few years — that, and not slow buildup in the minors has been what’s held his IP totals down recently. He appears both healthy and locked in right now, and the A’s need him if they’re going to have a shot at a Wild Card spot. He likely only gets some rest if the A’s have nothing to play for.


Jordan Montgomery (New York Yankees)

2021: 114.2 IP (Pace: ~165 IP) / 2020: 44 IP / 2019: 7.2 IP

Jordan Montgomery (and many others below him) made this list because he met my criteria, but he’s mostly here to give context to others that we might be worried about. The Yankees have no reason to shut him down while being short on pitching and chasing the playoffs. He’s also going to make a gigantic leap in innings, just like many other pitchers here. Shutdowns and limits are about limiting the risk of losing future wins for teams, not strictly about what’s best for players — if Montgomery played for the Orioles, there’s a good chance we’d be talking about something different.


Corbin Burnes (Milwaukee Brewers)

2021: 106 IP (Pace: ~160 IP) / 2020: 59.2 IP / 2019: 71.1 IP

Corbin Burnes‘ COVID IL stint early in the year puts him behind the other two Brewers aces in terms of rest risk. He’s still making a substantial jump, but they’re going to need him in the rotation as long as their games matter. I’d think he’s also the least likely of the three to have a start fully skipped in the last week if they have to prioritize: they might not have the arms available to rest three pitchers, so mileage this year will matter.


Tyler Mahle (Cincinnati Reds)

2021: 111.2 IP (Pace: ~160 IP) / 2020: 47.2 IP / 2019: 138.2 IP

Tyler Mahle is yet another “here because he hasn’t thrown 150 before” arm. I have no concerns about Mahle even when ignoring the Reds’ push for the playoffs, and with that in mind, he’s even less likely to be shut down. If they are eliminated, though, he’s a candidate for a last-week skipped start, though.


Lance McCullers Jr. (Houston Astros)

2021: 101.2 (Pace: ~155 IP) / 2020: 55 IP / 2019: 0 IP

Take everything I wrote about Luis Garcia and double the doubt that he’s shut down. The Astros might have the opportunity to rest Lance McCullers Jr. once their games become academic, and his past injury history means he might be a slightly higher priority than others to get that rest. He’s unlikely to rest before then. Rinse, repeat.


JT Brubaker (Pittsburg Pirates)

2021 : 102.1 IP (Pace: ~ 150) / 2020: 47.1 IP / 2019: 27.2 IP

JT Brubaker is in the midst of an innings jump that would certainly have us worried in normal circumstances. The Pirates also have enough rotation arms to give everyone a little extra rest as the year goes on. Just sticking with a six-man rotation might be enough to get them over the finish line, though, and the lack of news about any shutdowns or limits should probably be read as a sign that there isn’t one coming.


Eduardo Rodríguez (Boston Red Sox)

2021: 99.2 IP (Pace: ~145 IP) / 2020: 0 IP / 2019: 203 IP

I’m very glad to be able to include Eduardo Rodríguez on this list. He’s here because he’s been healthy and able to look like his old workhorse self after what was one of the scariest missed seasons a pitcher has had in recent memory. Ignore his ERA — between BABIP and LOB%, he’s been horrifically unlucky on the field in some ways that have had escalating effects and made him look about 2 runs per nine worse than he actually is. Expect him to finish strong and be a key piece of Boston’s playoff chase.


Taijuan Walker (New York Mets)

2021: 99.1 IP (Pace: ~145 IP) / 2020: 53.1 IP / 2019: 1 IP

Well this is a nice surprise, isn’t it? Taijuan Walker is likely to land around that 150 IP mark that I’m roughly using as a cutoff, but his injuries over the past few years make him a bigger red flag. On the other hand, the Mets have more games left to play than anyone else in baseball, and their other pitching injuries will mean that they’ll need him to start on a regular schedule likely until the playoffs end for them. He did sign a multi-year deal, so they should have his career in mind as they push him more so than some other returning-from-injury veterans, but he’s still likely to make the rest of his starts as long as the Mets have something to play for.


Jameson Taillon (New York Yankees)

2021: 100.2 IP (Pace: ~145 IP) / 2020: 0 IP / 2019: 37.1 IP

Taillon’s long recovery window from his Tommy John surgery has meant that he’s had fewer limits than he could have dealt with if he’d had the surgery in the late 2019 offseason. The Yankees also desperately need him still, and with Luis Severino and Corey Kluber, there’s just no other choice for the foreseeable future but to roll Taillon out there. Domingo German’s shoulder injury only makes things more complicated. It would be great news for the Yankees to have enough other healthy arms and a healthy-but-tired Taillon in a month. Bet against a shutdown.


James Kaprielian (Oakland Athletics)

2021: 77 IP (Pace: ~130 IP) / 2020: 3.2 IP / 2019: 68 IP

Oakland’s James Kaprielan is on pace to nearly double what he’s done before in his career, but he’s also far behind most of the rest of the Oakland rotation in innings pitched this year. And should he land in the 130-140 inning range that he’s currently on pace for, he’d still be far behind where many other young starters on track for shutdowns are expected to end the year after efforts to slow their season. Expect Oakland to use him as long as they need him, which should be until the very end of the regular season at the very least.


Shohei Ohtani (Los Angeles Angels)

80 IP (Pace: ~130 IP) / 2020: 1.2 IP / 2019: 0 IP

Joe Maddon has reiterated at multiple points that Shohei Ohtani has no limits this year. I have no words for that. Maybe he isn’t human? It sure seems like that’s the case. We consistently talk about how pitchers expose themselves to injury by batting, so maybe it’s less of a surprise that Ohtani has missed a handful of starts because of minor injuries. That’s the only thing that will hold him back on the mound as he chases an unprecedented MVP season.


Triston McKenzie (Cleveland Future Guardians)

2021: 84.2 IP (Pace: ~125 IP) / 2020: 33.1 IP / 2019: 0 IP

Triston McKenzie’s innings in the minors have been the stuff of legend in the past: in 2017, he put up 186 strikeouts over 143 innings at High-A. Because he missed the entirety of the 2019 season with a back injury, though, that record of endurance is in the past, and we do need to see him do it again. The biggest issue with McKenzie this year, though, is that he hasn’t shown often enough that he’s been effective enough at getting batters out to put up a big innings total. It’s possible that Cleveland keeps him in the rotation for the rest of the year to give him time to figure things out, but it’s also possible that they shut him down somewhat early to keep him from pressing. With his pace placing him on a track for a manageable total, though, the former seems more likely for now.


Shane McClanahan (Tampa Bay Rays)

2021: 77 IP (Pace: ~120 IP) / 2020: 0* IP / 2019: 120.2 IP

The Rays took their time building up Shane McClanahan this season, allowing him to get the most out of what could be a limited number of pitches this year. McClanahan’s 2016 Tommy John surgery still looms large over how he’s evaluated — and how could it not, given that he throws harder and more violently than almost anyone else from the left side. That said, he’s just not on pace to exceed any of his past totals by enough to raise red flags even including playoff starts. Tampa Bay will almost certainly be able to push him as they vie for first in the crowded AL East.


Alek Manoah (Toronto Blue Jays)

2021: 65.1 IP (Pace: 115 IP) / 2020: 0* IP / 2019: 125.1 IP

Alek Manoah’s late start to the year and recent back injury are doing most of the work to keep his season-long workload down. His unexpected and incredible performance this year has also been essential to Toronto’s odds at earning a Wild Card spot this year. He’s here not only because of his incredibly thin professional track record but also because the acquisition of José Berríos means that the Blue Jays have the six starters required to potentially get him some extra rest at times. It’s worth remembering, though, that Manoah pitched 108.1 innings for the University of West Virginia in 2019 before jumping up to the pros, so if he hasn’t been paid to throw 100 innings before, we shouldn’t be expecting him to be babied too much.


Photo by Jeff Robinson/Icon Sportswire | Adapted by Justin Paradis (@JustParaDesigns on Twitter)

Alexander Chase

When he's not writing about baseball (and sometimes when he is), Alexander Chase teaches test prep and elementary through high school math. He loves Shohei Ohtani, Camden Yards, and the extra-innings ghost runner rule. Don't you?

One response to “Analyzing Every Potential Starting Pitcher Innings Limit for 2021”

  1. TJ says:

    Excellent analysis, thanks!

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