On July 31, the Cardinals made a season-defining move. In a move that simultaneously freed up a spot in the outfield and changed the dynamic of the team, they sent Tommy Pham to the Rays in exchange for three minor leaguers. It was, to put it mildly, not the kind of trade you see very often. While he was in the midst of a down year, Pham was undoubtedly an electric player, one of the very best players in the major leagues when healthy and right. At the time of the trade, Pham was undoubtedly scuffling. Still, it was a tough trade to rationalize for many Cardinals fans. Takes were had. Tears were shed. Instagram Lives were shared. Time, as it does, moved on. Two days later, Pham was hit in the foot by a pitch in his second game with the Rays. Within a day, Pham hit the disabled list, and the team suggested he could miss as long as a month in recovery. It would be easy to imagine Pham’s season ending right there, and the Cardinals were similarly hanging onto postseason hopes by a thread.
A funny thing happened on the way to the offseason, however. The Cardinals surged into the second Wild Card spot before fading down the stretch. Pham returned after only 15 days, a remarkable turnaround. From the time he came back until the end of the season, Pham hit a scorching .355/.452/.645, good for the third-best wRC+ in baseball (Luke Voit, unbelievably enough, finished second behind Christian Yelich). In all, he accumulated 2.5 WAR with the Rays, comfortably more than the 1.5 he accrued on the Cardinals in more than twice as many plate appearances. So what happened? What turned Pham from a passable but unexciting hitter (.248/.331/.399, 101 wRC+) into essentially Babe Ruth (career line: .342/.474/.690, 197 wRC+)?
The first place to look when you’re wondering about an average-powered hot streak is the balls in play. Just as you’d expect, Pham’s BABIP was a gaudy .442 on the Rays. Case closed, right? Well, not exactly. First, there’s the fact that even if you plug in his career BABIP in place of this season’s crazy one and apply a little regression to the mean to his power, he’d still slash .277/.398/.537, which would put his wRC+ in the 160 range. Clearly, there was more to Pham’s resurgence than hitting a few baseballs to a gap in defenders. One of the most eye-popping numbers from Pham’s partial Rays season was his power. His Isolated Power (slugging percentage minus batting average) was a whopping .280, 80 points higher than his career average. It’s obviously only a partial season, but .280 would have been eighth among hitters with 300 PA this year. Whatever Pham’s other talents, he’s never been quite the power threat that he was in Tampa.
When I see a sudden spike in power, I think swing change. After three years of articles about it on Fangraphs, it’s something of a natural reaction. A quick look at Pham’s batted ball data doesn’t do much to change my preconception, either; Pham’s ground ball percentage was 37.3% on the Rays, significantly lower than the 50% he’s averaged for his major league career. In fact, the only two previous times Pham has had a lower ground ball percentage were in AA in 2016 (17 PA) and in rehab in 2018 (4 PA). Suffice it to say, Pham started putting the ball in the air a lot more. There’s always a question of classification, as line drives and ground balls can blend into each other, so I went to Baseball Savant for a little visualization. Here are Pham’s batted balls on the Rays:
That’s a pretty gorgeous set of launch angles. No wonder he’s hitting for power- every ball is coming off his bat at an ideal launch angle. For comparison, here’s how Pham’s launch angles looked on the Cardinals:
It’s pretty remarkable how different these two sets are. On the Rays, there’s just very little below 0 degrees, and they are probably mostly mishits, as no one hits a ball at negative twenty degrees on purpose. In 2017 on the Cardinals, Pham finished 12th in the majors in ground ball frequency among qualified hitters. Pham’s Rays ground ball percentage would be 30th-lowest. In short, he’s hitting the ball completely differently. Just to verify that it’s not an optical illusion, I did a quick T-Test on the two distributions of launch angles. Let’s just say it’s pretty unlikely that they’re the same (it’s significant at the .1% level).
This is a pretty bizarre finding. It’s one thing to change your swing in the offseason. Tampa is a data-driven team; maybe they’ll attempt something like this with Pham in the offseason. It’s just not happening in-season, though. What’s up here? Well, one thing that’s happening is that things are about to get a little abstract. Brooks Baseball has an excellent visualization of where in the zone a batter’s swings occur. Here’s a look at Pham’s swings by zone with the Cardinals (2017-2018):
Without context this can be hard to understand, but basically Pham swung at pitches in the strike zone with equal frequency high and low. He chased a bit below the zone, and mostly didn’t swing at pitches away. Let’s contrast that with his swing heatmap on the Rays:
Now, disclaimers are necessary here. Pham didn’t swing that often with the Rays. Pham didn’t even see that many pitches with the Rays! We’re talking about a few months of data here. Still, I’m pretty sure that this isn’t an accident. Pham has seen 27 pitches directly above the strike zone in his time with the Rays. He’s swung at eight of them. With the Cardinals in 2017 and 2018, he saw 186 pitches against the strike zone- seven times as many. He swung at 14 of them. Why should we care about this change in what Pham swings at? Well, take a look at which of Pham’s swings have turned into ground balls in his career:
So, there you have it. Since going to the Rays, Tommy Pham seems to be trying to hit less ground balls. He’s not doing it with a swing path. He’s doing it with his decisions. The new Tommy Pham has turned into a line drive and fly ball machine. Will it hold in 2019? Will pitchers adjust? I’m going to tune in to find out, but I’d totally understand if you don’t want to. Pham isn’t on the Cardinals anymore, after all. That doesn’t mean he isn’t interesting, though.
One thing I’ve heard people ask about Pham, aside from how he’ll do next season, is whether the Cardinals would have made the playoffs if they hadn’t traded him. First of all, as I laid out above, it really looks like he changed his approach on the Rays. Who’s to say what would have happened if he stayed on the Cardinals? Let’s ignore that for a quick second, though. What if the at-bats that went to Tyler O’Neill, Yairo Munoz, and Jose Martinez went to Tampa Bay Tommy Pham instead? I did a quick count of the math to find out. Pham had 174 plate appearances with the Rays. To create those PA’s on the Cardinals, we’ll simply replace 58 plate appearances from each of the three other outfielders who would have played in his stead. Defense? Yeah, we’re ignoring that. Baserunning? What am I, some kind of baseball analyst? Let’s stick to hitting, okay? So, 58 plate appearances from Tyler O’Neill. He ran a 123 wRC+ in August and September- nice! 58 from Jose Martinez’s 130 wRC+- we’ll take it. Finally, 58 from Yairo Munoz, who ran a 92 wRC+ over the time frame. Well, yeah, that one wasn’t great. That one’s on Shildt. Plugging these into a wRC+ to runs converter, the trio created 24.2 runs (in expectation) over that time. Tommy Pham’s 191 wRC+ works out to 40.5 runs created, a 16 run improvement. Just to get to a clean two wins, let’s assume that Martinez and O’Neill take some extra PA’s if Pham stays, pushing Matt Adams and Adolis Garcia a little deeper into the bench. That’s about as much as you can make Pham worth, though. Two wins over a tandem that already combined for a 115 wRC+ is no slouch, but the Cardinals finished three games out of the postseason this year. It looks like even if Pham were on the Cardinals, they would have finished juuuuuust out of reach.