Loading... Please wait...

John Dewan's Stat of the Week

Stat of the Week: Who Were the Top Overachievers & Underachievers in 2018?

Posted by

By Mark Simon

Who were the overachievers and underachievers of the 2018 MLB season?

It’s a question to consider for those evaluating their teams and conducting their fantasy drafts. Though there are no guarantees that the numbers will even out and that the player will return to his expected norms, understanding who overachieved and underachieved provides context to a player’s past performance.

Our defense-independent batting statistics (DIBS) can give expected results on every ball in play for a hitter by comparing the ball's trajectory, direction and velocity to other similar batted balls and assigning value based on those results. We can then compare those to his actual offensive numbers to determine if a player underachieved or overachieved.

In other words, these numbers can tell us if a player may have hit into hard luck, played in an unfriendly ballpark, or been the victim of some good defense. Or perhaps he hit into good luck, got a few ballpark-friendly hits, or took advantage of some poor defense.

Here's a look back at several players from 2018, along with their projections for 2019.

Overachievers

Before the start of last season, Mookie Betts made the underachiever list. He was coming off a 2017 in which he hit .264/.344/.459 when the batted-ball profile was that of a .297 batting average and .886 OPS hitter. It was noted then “There’s not much reason for concern, and at 25 he should be an MVP-caliber player.”

Much that went against Betts in 2017 turned in his favor in 2018. He won AL MVP honors in 2018, though the data indicated his numbers were better than what they likely should have been.

Betts hit 32 home runs, six above expectations, and 47 doubles, nine above expectations. His 1.078 OPS was 133 points higher than expected, though even if it had just met expectations (.945), he still would have had a great season. The 133 points were the most above expectations for any player with at least 250 plate appearances in 2018.

Betts was joined by J.D. Martinez and Steve Pearce in having the biggest positive differential between expected OPS and actual OPS. Martinez’s OPS was boosted by hitting 43 home runs, 10 more than the data indicated he was expected to hit.

Betts' 2019 projection: .303 BA, .923 OPS, 29 HR in 614 AB

Martinez's 2019 projection: .294 BA, .929 OPS, 36 HR in 555 AB

Pearce's 2019 projection: .262 BA, .806 OPS, 14 HR in 313 AB

The player with the highest OPS above expectations who wasn't on the Red Sox was Carlos Gonzalez, who hit .276 with a .796 OPS last season. Gonzalez’s batting average and OPS were 41 and 105 points above his expected performance respectively. Gonzalez was likely helped by Coors Field, where he hit .315 with a .941 OPS compared to .241 and .663 on the road. He’ll move to less-friendly Progressive Field as a member of the Indians in 2019.

Gonzalez 2019 projection: .271 BA, .814 OPS, 24 HR in 542 AB

Giancarlo Stanton is the one other player whose 2018 OPS was at least 100 points above expectation. Yankee Stadium likely helped a bit here as Stanton’s 38 home runs were seven more than the batted-ball data suggested he would hit. He had never been more than three home runs above expectations in a season while with the Marlins.

Stanton 2019 projection: .260 BA, .887 OPS, 42 HR in 574 AB

Underachievers

Angels shortstop Zack Cozart hit .219 with a .658 OPS while dealing with injuries in 2018, not what the team had in mind when it signed him to a three-year deal last offseason. Cozart’s numbers were a bit out of whack given where he hit the ball and how hard he hit the ball.

His expected batting average and OPS were .287 and .819 respectively. The 161-point differential between his OPS and expected OPS was the biggest negative differential between those stats in MLB.

Cozart’s 2019 projection: .259 BA, .744 OPS, 13 HR in 421 AB

Dodgers center fielder A.J. Pollock is another player whose numbers should have looked a little better. His .800 OPS in 2018 was 106 points below what was expected from his batted balls. Pollock, who finished his tenure with the Diamondbacks in 2018, may have been hurt by Chase Field’s humidor, as the ballpark was not the hitter-friendly place for right-handed batters that it had been in the past. It will be interesting to see how Pollock performs with his new team, the Dodgers, in 2019. His projected OPS (noted below) is right in line with his 2018 OPS.

Pollock’s 2019 projection: .266 BA, .804 OPS, 19 HR in 466 AB

One of the top prospects last season was Marlins center fielder Lewis Brinson, who hit a disappointing .199 with a .577 OPS in just over 400 plate appearances. Brinson should have been something closer to an average player in 2018 as his batted balls merited more home runs (15 expected, 11 hit) and a higher BABIP (.322 expected, .257 overall).

Brinson’s expected batting average and OPS for 2018 were .242 and .697. He got off to a hot start this spring and it will be worth watching to note if there is any carryover into his 2019 season.

Brinson’s 2019 projection: .219 BA, .644 OPS, 13 HR in 398 AB

A reminder that you can purchase the updated 2019 Bill James Player Projections at this link

SABR Analytics Conference 2019 Recap

Hundreds of baseball industry types and statistically-inclined fans descended on Phoenix this past weekend for the 2019 SABR Analytics Conference. It was two-plus days of former players, analysts, industry professionals, and students discussing the state of analytics in the game and presenting new research to push the conversation forward. [...]

Read More »


Running on Bryce Harper's Arm

By Mark Simon One of the storylines to follow for new Phillies outfielder Bryce Harper this season will be how he fares defensively. Harper’s defense cost the Nationals 26 runs last season, tied with new teammate Rhys Hoskins for second-worst in the majors. Harper struggled defensively in both right field, where he’ll likely play for the [...]

Read More »


Bill James Player Projections Updated

With spring training underway, the most popular question in baseball is “How good is he going to be?” It can be applied to hitters, pitchers, stars, hidden gems, prospects, and just about anyone [...]

Read More »


The Rise Of Outfield Shifts

By Mark Simon This offseason there was a lot of talk about the possibility of banning infield shifts, though that has yet to happen. It should be noted that teams aren’t just getting creative with their infield positioning these days, they’re also doing unusual things with their outfield positioning. BIS defines an outfield shift as when the [...]

Read More »


Stat of the Week: How Good is Kyler Murray?

Last week’s Stat of the Week covered the SIS rankings and stats for the top players available in this year’s [...]

Read More »


Stat of the Week: NFL Draft Top Prospects

With the football season over, it's time to shift attention to the future and the upcoming NFL Draft. In recent years SIS has tracked NFL and FBS games in a [...]

Read More »


Stat of the Week: ​Previewing the Super Bowl Offenses

There are expectations that Super Bowl LIII between the Patriots and Rams will be a high-scoring contest. The Rams ranked second in the NFL in points scored during the regular season. The Patriots ranked fourth. With that in mind, here’s a look at keys to the offenses in this game for each team.Patriots offensive key: [...]

Read More »


Congratulations to Bill James and Rob Neyer!

My good friends, Bill James and Rob Neyer, both received great recognition for their work recently.I have known Bill for the last 35 years. When I first read his work in the Baseball Abstract series way back then, it hit me. Bill was doing the exact kind of work with baseball numbers that I was [...]

Read More »


Stat of the Week: Active Players on a Hall of Fame Path

With this year’s Hall of Fame class announced, here’s a look at which active players have cleared the bar of Bill James’ Hall of Fame Value Standard. As a reminder, a player’s Hall of Fame Value (HOF-V) is his Win Shares plus four times his Baseball-Reference Wins Above Replacement (WAR). The standard for Hall of Fame [...]

Read More »



Sign up to our newsletter

Recent Updates