In 2023, Gunnar Henderson completed his first full season in the majors in spectacular fashion by winning American League Rookie of the Year. The former #1 overall prospect helped the Baltimore Orioles win 101 games and the AL East with an .814 OPS, 6.2 bWAR and 28 homers across 150 games. 

While Henderson did just about everything you could want from a rookie, there was one clear area for improvement as we entered the 2024 season: hitting left-handed pitching.  

Henderson had an .885 OPS when he saw a right-handed pitcher, but the left-handed hitter was much worse when he had to hit lefty-on-lefty, posting an OPS of .618 in those matchups. Henderson was one of 46 hitters with at least 100 left-on-left plate appearances in 2023 and his OPS ranked 38th among those hitters. 

The struggles against left-handed pitching weren’t exactly a surprise, given that Henderson had never been particularly impressive against them in the minors. In 2021, his OPS against LHP was .642 and his 2022 OPS against lefties between AA, AAA and the majors was a similarly pedestrian .670. Henderson entered 2024 with zero full professional seasons with an OPS above .700 against left-handed pitching. 

However, this year has been a much different story for Henderson and lefties. Henderson’s OPS against left-handed pitching has absolutely skyrocketed to 1.063, an absurd increase of 445 points from last year’s underwhelming figure. Henderson hit three homers in 167 PAs against lefties last year and this year he’s already hit the same amount of left-on-left homers after 48 PAs.  

There are 35 players who had at least 100 left-on-left PAs last year and at least 20 left-on-left PAs to begin this year and Henderson has seen the second-largest improvement to his OPS hitting left-on-left. He only trails another young shortstop who plays his games on MASN: CJ Abrams. 

Henderson has the third-best left-on-left OPS among those with at least 20 PAs this year and is one of just five hitters whose OPS is above 1.000. In fact, Henderson is so productive against lefties that he currently has reverse platoon splits with an .896 OPS against right-handers. 

Unsurprisingly, Henderson’s improvement against left-handed pitching is also backed up by data from Statcast. In 2023, Henderson’s average exit velocity against LHP was 87.0 MPH and now it’s 93.3 MPH. The increase in exit velocity has also come with an improved hard-hit rate, as that figure has risen from 34.6 percent to 50 percent. 

Henderson’s improvement against lefties can also be explained by how often he elevates the ball. In 2023, Henderson hit a grounder 51.4 percent of the time when he put the ball in play against lefties and now he’s trimmed that down to a ground-ball rate of 33.3 percent.   


Of course, when looking at trends in April we also need to acknowledge the sample size. Henderson’s production is a very encouraging sign, but we’re still looking at a sample of just 48 PAs. Sometimes a hot April can signal a breakout like 2021 Cedric Mullins and other times it just makes you 2023 Jorge Mateo.  

During 2023, the only batter to maintain a left-on-left OPS above 1.000 in over 100 PAs was Freddie Freeman. Meanwhile, Yordan Alvarez came the closest in 2022 with a .998 OPS. Since 2000, there have only been 18 occasions where a left-handed hitter faced a left-handed pitcher at least 100 times and provided a four-digit OPS and four of those seasons belong to a gentleman named Barry Lamar Bonds. Another three of those seasons were accomplished by Todd Helton, who certainly got a boost from where he played his home games. 

While it’s quite possible for Henderson to maintain this pace until October, it’s worth being realistic that this level of production has a good chance at cooling off at some point. However, there’s still quite a gap between 2023’s .618 OPS and his current 1.063 OPS where Henderson can still improve from last year without providing production that’d put him in the same company as someone like Bonds. 

In 2023, the league-average OPS for left-on-left was .689 and this year it sits at .666. If Henderson ends the year with a left-on-left OPS of something like .800, then it’d still be a major improvement from last season and make him an above-average hitter in those situations. Even if he really regresses towards an OPS closer to .700, being a league-average hitter left-on-left still makes Henderson an excellent player given everything else he offers. 

Last year we saw what Henderson can accomplish while struggling with left-handed pitching and now we’re seeing what it looks like when he crushes lefties. If these improvements are even remotely sustainable then one of the Orioles’ best young players has wasted no time getting even better.  

Rose Katz
Rose Katz

BSL Analyst

Rose Katz is a recent graduate of the University of Maryland’s journalism school, where she worked for The Diamondback as the online managing editor and a sports blogger. As a student, she spent almost all of her time on campus in The Diamondback’s newsroom or at Xfinity Center, Ludwig Field and Maryland Stadium. Rose gained intern experience with the Mid-Atlantic Sports Network (MASN).