In the long arc of baseball history, there is no precedent for Marcus Semien. Spend a day checking the statistical record: you won’t find anyone like him.
From 2013 to 2018, Semien produced a triple-slash batting line of .249/.310/.403. Adjusted for league and park effects, that tallies to an Adjusted OPS (OPS+) of 96. Semien’s Weighted Runs Created Plus (wRC+) was identical: 96.
That 96 is a percentage, of course: it measures his offensive production against the league average. Marcus Semien’s skills as a hitter, adjusting for park effects and league contexts, were a few ticks below the major league average.
His OPS+ and wRC+ were again identical last season: 91 and 91. During the weird 2020 season, Semien was again a slightly-below-average hitter. That is seven seasons of Marcus Semien’s hitting registering as passable, but not noteworthy. Seven years of hitting OK…for a shortstop.
And then there is Semien’s 2019 season, when he rated as one of the absolute best hitters in baseball. Over 162 games and 747 plate appearances, Marcus Semies was an utterly different player. His OPS+ was 139, good enough to tie for 9th in the league. His wRC+ was 138. He was – very suddenly - an elite hitter.
Here are those numbers in graph form:
|
Year
|
OPS+
|
wRC+
|
|
2013
|
80
|
79
|
|
2014
|
93
|
91
|
|
2015
|
98
|
97
|
|
2016
|
99
|
98
|
|
2017
|
97
|
97
|
|
2018
|
95
|
97
|
|
2019
|
139
|
138
|
|
2020
|
91
|
92
|
There is no other player in baseball history who can combine that discrepancy with so much playing time. Ozzie Smith was an average-ish hitter who got better, but his OPS+ peaked at 112. Zoilo Versales peaked at 115 during his MVP season in 1965. Luis Aparicio peaked at 114. Chone Figgins peaked at 117 and had another year at 110. Ten percent better than the league average is good, but it doesn’t qualify as elite.
You can find pitchers and part-timers who have nice runs, but it is difficult to find a player who can claim one year of elite hitting against a career of mediocrity.
What’s more interesting is that Semien’s statistical record doesn’t lend any very obvious reason for it. We might expect that Semien got incredibly lucky in 2019, but he didn’t have extraordinary luck on balls in play: his BABIP was .294 during his breakout season, .291 for his career). He also didn’t change parks or teams: he didn’t find himself thriving in a new environment or under new coaching.
The substinative change – using the word ‘substantive’ loosely – is that Semien’s walk rate got a little better, and he struck out a little less often. But even that doesn’t explain how his hitter suddenly paralleled J.D. Martinez. His exit velocity increased slightly, and he ‘barreled’ more balls (7.4% from a career average of 5.1%), but he reduced his launch angle on balls-in-play. His groundball-to-flyball ratio was unchanged, his pull/opposite rate was neutral, and his line drives actually decreased a bit. His discipline on pitches didn’t change he swung at the same percentage of pitches outside the zone and in the zone, and he made contact at the same rate as previous years. Pitchers threw him the same assortment of pitches, at the same velocity, and balls left his bat at the same speed.
Framing all of that differently: if you started by looking at the very insider-baseball, balls-in-play metrics that are far down on his FanGraphs page, you wouldn’t expect to see the dramatic difference between the Marcus Semien who played in 2019, and the Marcus Semien of 2013-2018, or 2020.
But the difference is there on the first page of statistics: Semien had a full year where he was an elite major league hitter.
So what can we expect going forward?
Broadly, there are two possibilities. One is the Semien’s 2019 season was a fluke, not discernible in the underlying metrics but an outlier campaign all the same.
The other possibility is that you can’t fake a full year with a 138 OPS+: it is a marker of ability that will show up again.
A player who is an interesting comparable to Semien - one player that might support the Blue Jays gamble - is future Hall-of-Famer Adrian Beltre.
Beltre had a career OPS+ of just 97 before his epic walk-year for the Dodgers in 2004. He followed that with a dud first year in Seattle, and didn’t really get back on his feet as an elite hitter until he signed with Boston as a thirty-one year old.
Let’s compare them:
|
Beltre OPS+
|
Semien OPS+
|
|
73
|
80
|
|
102
|
93
|
|
114
|
98
|
|
91
|
99
|
|
97
|
97
|
|
98
|
95
|
|
163
|
139
|
|
93
|
91
|
Beltre was younger than Semien: he was nineteen when he debuted in the majors, whereas Semien was twenty-two years old. And Beltre’s breakout season was massive: 48 homeruns, 200 hits, an OPS over 1.000. Semien’s 2019 season was terrific, but it wasn’t as eye-popping as Beltre’s breakout.
So what is it going to be?
FanGraphs has five projections for Semien posted so far, and his anticipated wRC+ ranges from 102 to 117. Two projections suggest he’ll be back around 100, while three split the difference between peak Semien and rest-of-his-career Semein.
Marcus Semien is one of the players I’m most interested in watching in 2021, because I don’t know what the answer is. Either we’re going to understand his 2019 season at one of the most unusual one-offs in baseball history, or his hit tool is going to show up again at some point.
What are you betting?
David Fleming is a writer living in southwest Virginia. He welcomes comments, questions, and suggestions here and at dfleming1986@yahoo.com.