Going Deep: The Sneaky Value of Marcus Semien

(Photo by George Walker/Icon Sportswire)

Throughout the offseason, I have participated in more mock drafts than I care to admit. In each one, I try a different draft position and new strategies. Whether I fill my infield slots early or wait on them until the late rounds, in nearly every draft I have taken the Oakland Athletics shortstop Marcus Semien. He’s going very late in drafts, often completely undrafted. He’s being taken as the 20th shortstop in NFBC (226th overall) and the 25th shortstop according to FantasyPros (262 overall). I believe that Semien is a diamond in the rough, potentially worth much more than a 20th round flier.

Semien has shown a key skill throughout his major league career: consistency. With a wOBA that has only varied between .311 and .315, The 27-year-old’s production has been like clockwork, even considering the wrist injury that caused him to miss half of the 2017 season. Save for the 27 home runs he hit in 2016—largely due to his outlieresque 14.7% HR/FB rate—Semien has been a safe source of around 20 home runs and 10-12 stolen bases. However, I believe that there may be another level that we have not yet seen from the unheralded shortstop.

The easiest source of an increase in production is an increase in opportunity. Semien has batted at the top of the Athletics lineup throughout Spring Training thus far and has reportedly been the favorite to lead off in 2018. Assuming he continues his hot start in spring games (.450 AVG, 9 hits in 20 at-bats) it seems very likely that Bob Melvin would entrust him with the first spot in the lineup. If this is the case, I am comfortable projecting Semien to score 95 runs in 2018. With a roster including Khris Davis, Matt Olson, and newly acquired Stephen Piscotty, I think a lot of people are mistakenly sleeping on the Oakland lineup.

Possibly my favorite reason to own Marcus Semien in 2018 is a notable uptick in his stolen base rate. Last season, in only 85 games played, Semien set a career high in stolen bases, swiping 12 bags in 13 attempts. His previous high was 11 SB in 155 games during his 2015 campaign. It has been noted by many analysts that changes in stolen base rate are mainly a result of choice. While increases in home runs, average, or on-base percentage are usually due to a change in approach at the plate, stealing a base is a choice made by the player or manager. Assuming Semien has decided to run more, it isn’t out of the realm of possibility that he sets another career high in stolen bases next season. His pace from last season would give him a total of 22 steals over 155 games. Pair that with his usual 20-25 HR, and you may have a top 10 shortstop on your hands.

The biggest downside to the A’s shortstop is his low batting average. Throughout his three full seasons in the majors, he has never hit better than .257. Much of this struggle has been rooted in his ineptitude against right-handed pitching. Batting only .230 and .231 against righties in 2015 and 2016, it was clear that a change in approach was crucial to any improvement in the future. And that seems to be exactly what he did in 2017.

Above is a visualization of Semien’s launch angle against RHP in 2016 and 2017. As you can see, the largest spike in his 2017 sample is resting between 10 and 20 degrees, notably lower than his 2016 mark that lies between 20 and 30 degrees. He has dropped his launch angle against RHP, preferring a line drive approach instead of hitting a lot of flyballs. His batted ball profile clearly reflects the change, as he’s raised his LD% against righties from 17.2% in 2016 to 20.9% in 2017 while lowering both his groundball and flyball rates over that same span.

Semien has also managed to lower is K% and increase his BB% against RHP over each of the last three years. The gradual changes in approach paid off in 2017 when he posted a .258 AVG, .743 OPS, and .322 wOBA against RHP, all career highs. If he continues these positive trends in 2018, Semien has a legitimate chance to post a career high in batting average, likely pushing the .260 mark.

Throughout his career, Semien has never topped a .257 AVG, or 12 stolen bases, or 72 runs scored. I believe that with a change in batting approach and a willingness to run, he could easily top all of those marks. My realistic—though a bit optimistic—projection for Semien in 2018 would be a .265/.330/.425 slashline with 20-25 home runs, 20-25 steals, and near 95 runs scored. That line is very similar to the season just put up by Elvis Andrus, the top shortstop of 2017. A couple key differences between Andrus and Semien is the batting average and RBI total will likely be significantly lower for Semien. Even so, with a strong 20-20 season, Semien would easily find himself amongst the top ten shortstops come season’s end.

I’ve seen no hype or even remotely good press about Marcus Semien within the fantasy baseball community this offseason, which only lends itself to the maxim, “No news is good news.” If Semien’s ADP stays in the mid-200 range, I will continue to draft him in every league that I play in and look forward to reaping the rewards come the regular season.