Joey Bart’s stunning Pirates power outage doesn’t make any sense

The Pittsburgh Pirates picked up Joey Bart early in 2024, and he ended up being a massive addition to the lineup and a huge change-of-scenery candidate who rebounded. He turned in a .265/.337/.462 triple-slash with 13 home runs and a 121 wRC+ throughout 282 trips to the plate. Bart was a big power threat, especially for a catcher. His .198 isolated slugging percentage was the sixth-best among all primary backstops with at least 250 plate appearances.

Bart was expected to be a potential middle-of-the-order presence this year, but his power has come up well short. Instead of maintaining his impressive pace, he is only slashing .234/.335/.288 with an 81 wRC+. The prodigious power Bart showed off last year has seemingly evaporated. He only has a single home run in 212 plate appearances, as well as an .054 isolated slugging percentage. His lack of offense has led to Henry Davis potentially overtaking him on the depth chart. A deeper dive into his stats only further makes his power outage more confounding.

What happened to Joey Bart's power?

Bart’s raw power is basically the same as last year. In 2024, he had an 88.1 MPH exit velocity and a 9.4% barrel rate. This year, he has an exit velocity of 88.2 MPH and a 9.4% barrel rate. He’s even improved in hard-hit rate, going from 38.7% to 41.4%. Looking at that, you’d probably think that Bart isn’t lifting the ball as frequently. This is partially true, but not to the extent you may think. Bart had a 10.5-degree launch angle last year and is at 9.4 degrees this year. That shouldn’t be enough of a difference to take a player who had an isolated slugging percentage of nearly .200 to well below .100.

His plate discipline has also been about the same as last year. He had a 25.9% K%, with a 7.8% walk rate, 26.2% whiff rate, and 26.4% chase rate during his 2024 season. Bart is striking out slightly more frequently this season, with a 26.4% K% and a 29.1% whiff rate, but his chase rate and walk rate have dramatically improved to 23.1% and 11.8%, respectively.

The best explanation may be found in his bat tracking data. According to Baseball Savant, Bart had a fast swing rate of 51% last year. A fast swing is anything with a swing speed above 75 MPH. However, Bart’s fast swing rate is down nearly 10% to 41.5% in 2025. However, his bat speed is still great at 74 MPH. 

Bart’s decrease in fast swings is likely the biggest culprit to his lack of power this year, but sluggers like Wilyer Abreu, Teoscar Hernández, and Shea Langeliers all have lower fast swing rates, and are hitting for plenty of pop. The fact he’s made such a change, while maintaining very similar exit velocity, launch angle, and barrel rates as last year shouldn’t result in a sudden dearth of power. Objectively, it's a very confusing problem.