The Dodgers are still alive in large part thanks to Adrian Gonzalez, and for Gonzalez, it’s been a series somewhat defined by the inside pitch. The crucial double he hit off Adam Wainwright — the double that would eventually lead to the manufactured, insufferable Mickey Mouse racket — was hit against an inside cutter off the plate, by the hands. In Wednesday’s Game 5, Gonzalez yanked a pair of solo home runs, the first giving the Dodgers a lead. In the bottom of the third, Gonzalez pulled an inside Joe Kelly fastball for his longest home run since 2009. In the bottom of the eighth, Gonzalez again went deep, getting in front of a high, inside John Axford curve. With Andre Ethier hurt, Matt Kemp genuinely out, and Hanley Ramirez effectively out, Gonzalez is feeling more pressure to deliver than usual, and he’s been a big part of what success the Dodgers have had.

The Dodgers, of course, expect Gonzalez to be a rock in the middle of their lineup, which is one of the big reasons they made that insane trade in the first place. And Gonzalez has the track record of being an underrated offensive superstar, and he’s still just 31 years old. He’s coming off a 124 wRC+, which isn’t fantastic, but which is good, and which is an improvement from the year before. But while Gonzalez can still hit and while he can still make a difference in a critical series, it’s interesting to observe how things have changed in the process. What Adrian Gonzalez was, he appears to no longer be.

My prime baseball-watching years in San Diego overlapped with Gonzalez’s turning into a star. He got good in 2006, he got great in 2009, and eventually he was part of a blockbuster deal across the country. What made Gonzalez stand out wasn’t unique to him, but it was always impressive how he managed to drive the ball to the opposite field. Gonzalez was a left-handed hitter who hit the ball out to left and left-center, and the numbers bear out how outstanding he was.

Between 2008-2010, Gonzalez slugged 48 dingers to the opposite field, and his isolated slugging percentage was .466, sandwiched between Ryan Howard and Joey Votto in second place. Granted, it wasn’t the easiest thing in Petco Park to hit a homer to right, but the other side wasn’t exactly a launching pad, so Gonzalez did what few could do. He started getting walked, more and more often, because he was the guy to fear in the Padres’ lineup, and he had power to all fields. As a hitter, Gonzalez was complete.

Then, between 2010 and 2011, Gonzalez had fairly significant shoulder surgery. Whenever a player gets a shoulder operated on, people speculate on how it’s going to affect the on-field performance. With Gonzalez, we don’t have to speculate anymore — we have a record of three years of on-field performance since. Gonzalez has changed, no longer in possession of what was his most distinguishing feature.

Between 2011 and 2013, Gonzalez still ranks ninth in baseball in isolated slugging the other way. But it’s gone down exactly 200 points, and he’s gone from hitting 48 dingers to left and left-center to hitting 18. He hit ten three years ago, he hit six two years ago, and he hit just two this most recent year. He’s also gone from hitting 22 homers to center to 11. To right field, however, he’s gone from 37 to 38 over consecutive three-year periods. The pull power is still there for Adrian Gonzalez. The rest of the power is not. Over those last three years in San Diego, 12% of balls hit the other way left the yard. Gonzalez has come in at 4% since.

What do we have? Howard Megdal caught up with Gonzalez just the other day:

“There’s some things that I was able to do when I had a healthy shoulder that I can’t do now,” Gonzalez told me on the field prior to Tuesday’s NLCS Game 4 against the Cardinals. “I mean, my shoulder is healthy, but I’m talking about before surgery.”

[…]

“As far as driving the ball to leftfield, letting it get deep, whenever I do that now, it gets caught at the warning track,” Gonzalez said. “So something’s gotta switch. Now, I’ve got to go to a more up-the-middle approach.”

These spray charts from Brooks Baseball are helpful. On the left, 2008-2010 Adrian Gonzalez; on the right, 2011-2013 Adrian Gonzalez. We’re most concerned with balls hit to left and left-center, and we should of course note that Gonzalez spent a lot of recent time hitting in front of the Green Monster.

If you’d like to eliminate the Green Monster variable, here’s 2009 Gonzalez and 2013 Gonzalez.

The balls hit to left and left-center are just shorter. Gonzalez understands what’s going on — he just doesn’t have his old strength the other way. Maybe it’s because of the surgery. Maybe it’s just aging, and the surgery isn’t it at all. It’s probably the surgery. But while Gonzalez is strong and healthy enough to play and produce, he can’t do what he used to. And now, especially since he’s out of Boston, he’s having to change, to deal with the changes.

In 2010, Gonzalez pulled 35% of his balls in play, and he hit 29% to the opposite field. These rates stayed more or less the same the next two years, because there was a big forgiving wall in Fenway that allowed even shorter drives to do damage. Maybe at that point it was more difficult for Gonzalez to notice his reduced power. His first full year in Los Angeles, though, he pulled 42% of his balls in play, and hit 24% to the opposite field. Gonzalez knows where his power is now, for the most part, and we can look at the pitches he’s hit out. This is a chart of Gonzalez’s 2008-2013 home runs, split up before and after the surgery.

Maybe some things aren’t immediately apparent. Of the 37 most outside pitches Gonzalez has hit out, just nine have been hit since 2011. Of the 41 most inside pitches Gonzalez has hit out, 26 have been hit since 2011. Gonzalez is less able to drive those pitches over the outer half, at least in terms of getting them over a fence, so he’s adjusted by turning on more baseballs, doing a better job of pulling his hands close and maiming pitches in. We saw him drill an undrillable pitch when he hit the double off Wainwright. The two homers Wednesday were inside, and Gonzalez hit one of them 450 feet. Gonzalez is in the process of figuring out how much he can do with his new body. It’s said that CC Sabathia is going to have to figure out how to pitch with less of a fastball. Gonzalez is working on how to hit with less strength in his shoulder, and it seems the solution is to focus more on going to right and right-center.

It’s not the approach that allowed Gonzalez to become a star, but there’s no benefit to his being stubborn and still trying to be the same player. That player can’t exist anymore, if the shoulder is indeed weaker than it was. So the Adrian Gonzalez who can hit now looks meaningfully different from the Adrian Gonzalez of the later Padres days. By stance, he’s the same, and by swing, he’s similar. Watch him for just a few minutes and you might not pick up on the changes, because they’re overall pretty subtle. But Gonzalez is trying to maximize the strength he has left. To a cynic, maybe this means the beginning of the end, but try telling that to the Cardinals.