Going Deep: Marco Gonzales Was Good, But He Can Be Even Better

(Photo by Keith Gillett/Icon Sportswire)

Marco Gonzales ended the 2018 season nearly as unappreciated as he began it. After being selected 19th overall in the 2013 MLB draft, he has missed a significant portion of 2015 due to shoulder issues, and all of 2016 and parts of 2017 due to Tommy John surgery. Gonzales is just shy of 27 years of age.

Despite missing out on massive amounts of time during critical periods in his development, Marco Gonzales has thrived nonetheless. After pitching just 76.4 major league innings across a span of four years, Gonzales helped to stabilize the Mariners’ rotation by tossing 166.2 solid innings last year.

Gonzales ranked very well amongst starting pitchers in 2018:

• 16th in FIP
• 18th in xFIP
• 39th in ERA
• 20th in fWAR

Let’s begin with a few comparisons! People love comparisons.

Name	IP	COM-	SIERA	fWAR	bWAR
Pitcher A	166.2	89	3.81	3.6	2.5
Pitcher B	207.2	84	3.60	3.5	4.8
Pitcher C	160.1	81	2.96	3.8	2.9

Okay, the perceptive folk will have noticed that Pitcher A is Marco Gonzales. His innings pitched is right above the table! One was obviously going to be Marco Gonzales. Pitcher B and C are trickier, though.

Pitcher B is Diamondbacks’ de facto ace Zack Greinke, picked because of a K-BB% and fWAR akin to Gonzales’, while Pitcher C is former friend and ace, James Paxton, selected because he has a similar bWAR to Marco Gonzales, shares ties to the Mariners, and has a penchant for also throwing with his left hand.

Now, the point of this is not to say that Marco Gonzales is James Paxton or Zack Greinke. He quite literally is not, and I don’t think he misses bats like peak Greinke or present Paxton, limiting his ceiling. xFIP- and SIERA say that Paxton was a much stronger pitcher in 2018 than Gonzales, and bWAR and ERA- say the same in regards to Greinke over Gonzales. However, I think it is important to look at these numbers in context. I’m not going to focus on Greinke or Paxton, because no one wants to read a 2500-word article. What is most important to me is that I show that it wasn’t necessarily a level playing field for Marco.

None of his success is happening by accident. In college, his changeup was regarded as one of the best, and in the minors, his changeup was also considered one of the best. His slow ball hasn’t changed. Most other things have changed!

Marco’s sinker is by far his worst pitch, but that isn’t surprising. Starting pitchers generally aren’t going to their sinkers as their out-pitch. Regardless, PITCHf/x has Gonzales’ sinker ranked fifth in starters, while Pitch Info has him 20th. Either way, his sinker ranks slightly above 0.0, which means it’s around average in run value. For a sinker, that’s fine! You’ll need some supplementary pitches, though.

Gonzales’ curveball *is* that supplementary pitch. Of his pitches that he threw last year, his curveball has seen the most substantial improvements. That’s not surprising! Before this season, he mentioned that his curveball was the most negatively impacted pitch in his repertoire since returning from Tommy John surgery. Not only is his feel for it back, but it’s one of his best pitches, and one of the better curveballs in the league. PITCHf/x ranks his curve 11th in the MLB, for pitchers (wCU/C).

What I am most fascinated by is the cutter that Gonzales introduced in 2018. Since his Tommy John procedure, his cutter has been missing from his repertoire because of the pressure it puts on his elbow. Now that he’s healthier, he’s been able to slowly mix it in. In April, it was his least thrown pitch, thrown only 15% of the time. By the end of the year, it was his *most* used pitch, offered 27% of the time. Featuring a new pitch that much is impressive enough, but Gonzales’ cutter produced an xwOBA of .274, the lowest of any of his pitches.

Gonzales has been able to have so much success not only because he mixes his pitches very well, but also because he is spectacular at making his pitches look like one another.

Here you go @jasoncollette…

Marco Gonzales, 87mph Cutter and 78mph Curveball (overlay). pic.twitter.com/ZgL20T7ixi

— Rob Friedman (@PitchingNinja) June 9, 2018

This gif is a perfect exemplification of how Gonzales uses the late break of his curveball to masquerade as his cutter, until it isn’t his cutter.

In 2017, Gonzales pitched 126.1 total innings. In 2018, he received a 31.8% uptick, throwing 166.2 innings. That’s a fairly sizable increase, and so I want to see how Gonzales fared after the ~126 innings pitched mark.

For one, Gonzales saw a steady decline in velocity from March to September. After peaking at an average sinker velocity of 90.7 mph in May, Gonzales was averaging 89.3 mph by September, nearly 1.5 mph less. At least anecdotally, the difference between 89 and 90 mph is much more significant than, say, 94 and 95 mph.

Another comparison!

Name	IP	COM-	SIERA	FBvelo
Marco A	125.2	82	3.72	90.3
Marco B	41.0	109	4.06	89.4

Upon meeting his 2017 IP threshold, Gonzales made one more solid start (in which his velocity was the lowest it had been since April) before posting several stinkers, giving up 23 earned runs over his next 19.0 innings. For those keeping score at home, that is bad! So, so very bad. But! A couple bad June starts and a truly dreadful August were Gonzales’ undoing, as he ended up stringing together a solid group of starts to finish out the year.

Not only that, but during the first period Gonzales’ 3.37 ERA was in line with his 3.35 FIP and 3.48 xFIP. During the second period — after he met his 2017 IP threshold — his ERA rose to a ghastly 5.93, while his 3.67 FIP and 3.94 xFIP remained respectable. That’s enough to leave me skeptical.

Now let’s compare Marco A to Greinke and Paxton.

Name	IP	COM-	SIERA
Marco Gonzales A	125.2	82	3.72
Zack Greinke	207.2	84	3.60
James Paxton	160.1	81	2.96

I think it goes without saying that this isn’t *exactly* how this works. You can’t take the best part of a pitcher’s year and simply compare it to two other pitchers’ entire years. That’s unfair! I don’t, however, feel it is disingenuous to say that Marco was a different pitcher upon pitching more innings than he has in a year since 2014.

It’s difficult to find any substantive changes in Gonzales’ profile, other than his velocity. His pitch mix did not markedly change, and he wasn’t especially unlucky. I see a drop in velocity — and with it a change in spin rate — and his release points tightened up, as have his pitch tunnels. His curveball’s spin rate, in particular, peaked at 2479 rpm and steadily dropped from that point until bottoming out at 2390 rpm in September. That is nearly a drop of 100, which is significant.

In March, Gonzales mentioned that he felt he was around 90-95% healthy, so it’s possible he could have spent much of the year pitching at less than full strength, but that’s pure speculation. In fact, the frequent implementation of his cutter hints otherwise — that he was mostly full strength, and the culprit was merely general fatigue. For reasons I expect are due to a dip in velocity, Marco Gonzales was great, and then he was not. He didn’t throw particularly hard, and then he threw even less hard. His pitches all graded out as positive or neutral, and then negative.

Gonzales was dreadful in his final 41 innings, but then there appears to be a logical reason for it, and his peripherals aren’t so bad anyhow. By the end of the year, Gonzales was neck and neck with Greinke and Paxton in fWAR and bWAR, respectively. His changeup was already regarded to some as plus-plus, but now his previously fringe curveball grades out as one of the best, and now he’s got a new shiny cutter to pair with it. He surely isn’t an ace, but at times, you could see him evolving right before our eyes. In 2018, you wouldn’t be lying if you said Marco Gonzales was like Zack Greinke and James Paxton in some ways. They don’t go about it exactly the same way, but going forward, it wouldn’t be crazy to say that Gonzales will end up something like Zack Greinke. He has the draft pedigree, after all, Marco is just finally healthy enough to showcase the skills that got him drafted 19th overall.

(Photo by Keith Gillett/Icon Sportswire)