Joc Pederson’s Improvement, In One Swing by Jeff Sullivan April 4, 2017 Joc Pederson hit a home run on Monday. It was a grand slam. It was, further, a tie-breaking grand slam, but it wound up a little bit lost, because Yasmani Grandal also hit a home run. And Grandal hit an additional home run. And Corey Seager hit a home run, too. The Dodgers beat the Padres by 11, and although no one is ever favored to defeat another club by 11 runs, Monday felt almost like a foregone conclusion. The Padres got whooped, and Joc Pederson was just a part of that. But, this — this is the time to over-analyze. So let’s do that! As far as I’m concerned, personally, Pederson’s grand slam made an impression, and I’d like to keep thinking about it. For Pederson, it was a new kind of pitch to take deep, and it speaks to how far he’s already come. I do understand that Pederson homered against Jhoulys Chacin, and that isn’t quite like homering against prime Roy Halladay. More, the count ran to 3-and-1 in Pederson’s favor, and Chacin delivered a fastball in a fastball count. But the pitch was still 92 miles per hour, and Chacin didn’t leave it hovering. Pederson didn’t get a fastball in his dead-red area. Chacin effectively found a corner, but the pitch was rendered ineffective at 111 miles per hour, leaving at an angle of 18 degrees. Kablammo! The pitch might well have been a ball, and that would’ve meant one run. Chacin would’ve gotten crap for walking in a baserunner. Yet given that Pederson attacked, the pitch clearly must’ve looked good enough, and when you examine the screenshot, you can see that Chacin might not have deserved to give up a bomb. The ball was over the edge of the plate, and at the level of Pederson’s front number. If you don’t know a lot about Joc Pederson, you don’t know what he prefers. That isn’t on you; you can’t know by heart the details of everyone. So, using Baseball Savant, I’ve made this easy. In this plot are all of Pederson’s career home runs, with Monday’s dinger colored in red. It’s out there by itself, high and tight. Like most hitters, Pederson prefers to get his arms extended, and his power swing comes against pitches comfortably over the plate. The Monday pitch didn’t turn into Pederson’s most inside home run, or his highest home run. Yet it might’ve been the most challenging home run, given how little time Pederson had to get the bat to the ball in order to hit it hard and fair. Pederson was required to shorten up. When he was a younger player, he was close to incapable of shortening up. The home run was made possible by Pederson keeping his hands in, and taking a mostly level attack path. There are two tricky things about that. For one, Pederson is more of a fly-ball hitter. During the Statcast era, he ranks in the 76th percentile in terms of average launch angle. Hitters like that tend to be more successful down, and more exploitable up, and Pederson has been no exception. The uppercut swing has more trouble against pitches at the belt. There was little uppercut to this particular swing — you can see that from Pederson’s follow-through. Call it luck, or call it anticipation, I don’t know. Pederson had the right swing for the opportunity. And for two, power hitters commonly have issues keeping their hands in. Pederson certainly had such an issue back as a rookie in 2015, but a year ago he took a step forward. It could’ve been linked to his getting better prepared for fastballs, but Pederson has worked hard to eliminate an inside vulnerability. Homers like Monday’s have become increasingly possible. Two years ago, among lefties, Pederson ranked in the first percentile in inside-pitch contact rate. That is, he was practically last. Last year, he jumped up to the 40th percentile. Still not great! But much, much better. And, two years ago, he ranked in the 67th percentile in inside-pitch exit velocity. Last year, he jumped up to the 96th percentile. Pederson is now better able to punish pitches closer to his body, and although Monday’s homer will never be the norm, it was another encouraging swing to see. That same home run would’ve been almost impossible to picture not even that long ago. Between the last two years, Pederson’s overall contact rate improved by nine percentage points. That’s a pretty extraordinary leap, and Pederson sacrificed none of his power to get there. It takes some careful execution to be able to pull something like that off, and, step by step, Pederson’s been making himself more complete. He does still probably strike out too much. He could put up more of a fight against lefties. Problem spots remain, and Pederson is no Kris Bryant. But that grand slam is indicative of something. That pitch could’ve been cut on and missed. It just as easily could’ve been popped in the infield. Pederson ripped a screaming liner, and in the game, the Dodgers never looked back. We’ll see where Pederson ultimately ends up, but he’s already ahead of where he used to be.