When Geraldo Perdomo Attacks

It sure seems like the Diamondbacks knew something the rest of us didn’t. Back in February, when Arizona signed shortstop Geraldo Perdomo to a four-year contract extension to keep him around through the 2029 season, I wrote, “I think the Diamondbacks are paying for floor rather than ceiling. However he gets there, if Perdomo keeps performing like a two-win player, the contract will work out well for both sides.” Perdomo was coming off a knee injury and two straight seasons of absolutely average offensive performance. It may have looked like the Diamondbacks were comfortable with that level of production, but the 2025 season has put things in an entirely new light.

Perdomo has been unequivocally one of the best players in baseball. He leads all National League position players in bWAR, and if not for Shohei Ohtani, he would have a very good argument for the MVP. Geraldo Perdomo, whom I first wrote about because he was a great test case for players with extremely low exit velocities. Geraldo Perdomo, whose offensive approach I summed up earlier this year as, “Try with all your might to avoid swinging.” Geraldo Perdomo, whose 12th-percentile hard-hit rate represents a career-high! That guy has 6.7 WAR. That guy has 19 home runs after coming into this season with a combined 14 for his major league career, which began in 2021. That guy is running a 138 wRC+ and none of the advanced numbers is saying it’s because of batted ball luck. Perdomo really has been a great hitter. We’ve been all over the story. Michael Baumann has written about him twice, I’ve broken down his breakout and documented one of his trademark swingless plate appearances. Now that October is near, we need to acknowledge how big a deal it is that Perdomo has kept this going all season long.

Perdomo has gotten bigger and stronger. He’s changed his mechanics from both sides of the plate. He’s somehow chasing and whiffing even less than he did last season, and he’s somehow doing so while lifting the ball more, swinging a bit harder, and hitting the ball a bit harder. We’ve broken down all those points in the articles I linked to above, so I’m not going cover that ground again. I’m here to show you one graph that cracks me up.

This is from the last paragraph of my article back in February: “I am so, so curious to see what it would look like if Perdomo were to start attacking the ball. He’s still young, and I really do think it’s possible that he has the capacity to be more than an average hitter.” I’m not trying to say I called this. I definitely did not. One sentence later, I wrote “Still, I don’t think we should expect that going forward.” But Perdomo really did start attacking the ball in his own way, so I can now show you what it looks like.

In terms of average exit velocity, it doesn’t look like all that much. He’s running a career-high 87.6 mph, up half a tick from last season. That’s still only enough to put him in the 19th percentile. However, you know better than to just look at average EV and call it a day. His 90th-percentile exit velocity jumped from 100.4 mph to 101.5. That’s a bigger jump, but in terms of percentiles, it only moves him from the 14th to the 18th. So, uh, that doesn’t look like that much either.

It’s impressive that Perdomo can swing harder, lift the ball more with a steeper swing, and maintain his absurdly high contact and squared-up rates. Regardless of where you’re starting out, that’s not normally how things work. But it’s also not enough to earn him respect. For all the reasons in the previous paragraph, pitchers still aren’t afraid of Perdomo, like at all. He ranks fifth among qualified players in zone rate. He’s seen 873 pitches over the heart of the plate. That’s the most in the game, and nobody else is even close. But Perdomo has the best hard-hit rate of his career by a wide margin, and that does matter. He’s never going to break the power scale, but let me show you Tom Tango’s graph for the thousandth time.

Going from a 25.8% hard-hit rate to a 31.5% hard-hit rate means crossing that threshold way more often. Even if you’re just barely crossing it, it’s still a big deal. There are way more hits on the right side of the line. The odds have changed on all those pitchers who are content to let Perdomo put the ball in play. Perdomo is still not a big, powerful guy, but he’s got a new A-swing. Here’s Baseball Savant’s distribution graph of his bat speed. This is for all swings.

Perdomo’s right-handed numbers from the 2025 season are in orange in the front. It’s still not as fast as the dotted line that represents the league average, and even though its peak is more than 1 mph higher than the peaks of the previous seasons, its shape doesn’t look all that different. It’s just that the tails on either side are fatter. That’s really noticeable on the left of the graph. Perdomo isn’t taking fewer super-weak, 57-63 mph swings than he did in previous seasons. What he’s cut down on are the medium-speed swings, and he’s getting off more fast swings than ever before. In other words, when he knows he has a chance to hit the ball hard, he’s making sure he does it. I know that looks pretty subtle here, and the difference between the green and blue areas that represent his 2024 and 2025 stats batting left-handed is even smaller. But now we’re getting to the graph I really want to show you, the one that has me cackling. Here’s the same exact thing, except it only shows the swings that result in hard-hit balls.

Well that’s different! Look how far the 2025 distributions are from the 2024 ones. The blue left-handed peak is roughly 2 mph faster than it was in 2024, and the orange right-handed peak is 5 mph faster! All of a sudden, Perdomo is getting his getting his money’s worth. He’s still happy to take a slow swing and put the ball in play – that’s why the tail on the left side of even this graph extends farther than in any of the previous seasons. But not only is he kicking into high gear more often, it’s a higher gear than he ever had before. Perdomo still doesn’t have the top-end bat speed to keep up with the league average on the right side of the chart, but he’s way above that dotted distribution line until we get to 77 mph or so. He’s more than doubled his fast-swing rate from 2024. That’s what it looks like when Perdomo starts attacking the ball, and it’s even more fun than we could’ve hoped.