Adrian Gonzalez’s Power Outage

When I published our updated first base tier rankings last week, I mentioned that Adrian Gonzalez had hit just 13 homers in his previous 478 plate appearances dating back to last year. That stretch is now up to 509 plate appearances, not all that far off from a full season’s worth of playing time. Considering that Gonzalez is in his prime (turned 30 two days ago) and moved out of Petco Park and into Fenway Park last year, the recent lack of power is a bit troubling.

The first red flag that comes to mind is his right shoulder — the power shoulder for left-handed hitters — which was surgically repaired (torn labrum) just prior to his trade to the Red Sox. Gonzalez admitted to Ken Rosenthal of FOX Sports that his shoulder was feeling weak and tired last September, but he recently told Pete Abraham of The Boston Globe that he’s healthy now…

Gonzalez also said he is fully healthy for the first time in several years. He had surgery to repair a torn labrum in his right shoulder after the 2010 season and felt the residual effects all last season.

“I had to have a bunch of cortisone shots and I had tendinitis and all sorts of stuff going on [last season]. It’s all in the past now,’’ Gonzalez said. “It’s 100 percent now. My shoulder is 100 percent.’’

The biggest change in Adrian’s performance last year came in his ability to hit the ball in the air, which may or may not be tied to the shoulder fatigue. We really don’t know. His day-by-day batted ball profile shows that his ground ball drop jumped to over 50% a few weeks into the season and essentially remained there…

The batted ball profile has been all over the map in the early going of 2012, but that’s to be expected after only 30 games. BIS data can be a little sketchy when it comes to balls on the fly ball/line drive bubble, but a ground ball is a ground ball and it’s impossible to hit the ball out of the park when you’re beating it into the grass. Let’s take a look at Gonzalez’s spray chart during this 509 plate appearances stretch with some help from Texas Leaguers…

First of all, teams should be shifting their infielders over to the second base side of the bag whenever Gonzalez is at the plate. The guy has a reputation as an opposite field hitter, but not when he puts the ball on the ground. Secondly, that opposite field power hasn’t been there over these last 509 plate appearances. Granted, four homers the other way during that time is more than most players will hit in a three-year span, but we’re talking about a guy that led baseball in opposite field homers (48) during his final three years with San Diego. That’s nearly 50% of his total homerun output during that time.

Perhaps the Green Monster is actually hurting Gonzalez rather than helping him, at least in terms of over-the-fence power. Maybe he’s hit some lasers the other way that would have cleared the wall by a few rows in other parks but hit off the top of the wall in Fenway, resulting in two bases instead of four. I don’t have any evidence to back that up, it’s just a theory. It is worth noting that Gonzalez has just a .101 ISO against left-handed pitchers during his homer drought, well below his career .164 ISO vs. LHP. CC Sabathia, David Price, and other AL East southpaws probably have a little something to do with that.

There’s really no obvious answer for Gonzalez’s recent decline as a power hitter. He says his shoulder isn’t bothering him and we have no reason not to believe him, though players do like about injuries basically all the time. Gonzalez remains tremendously productive overall — .308/.391/.460 during this admittedly arbitrary same of 509 plate appearances — but as a top tier fantasy first baseman, he’s got to hit for power. There are no exceptions; batting average and RBI only go so far. Gonzalez plays in a favorable hitter’s park and has a great lineup around him, so the RBI and runs scored opportunity will be plentiful. He just needs to start driving the ball over the fence again, because both Red Sox fans and fantasy owners are starting to get a little frustrated.

Side Note: I wrote this post about Giancarlo Stanton’s power outage last week, and he went on to hit five homers in his next seven games. You’re welcome in advance, Red Sox fans.