Adrian Gonzalez established himself as one of the game's great hitters by using his smooth, compact stroke to lash outer-half pitches to the opposite field. In fact, no active player this side of Jim Thome has a higher slugging percentage on outer-half offerings dating back to 2008 (.545). Against outer-half fastballs, Gonzalez has a .682 slugging percentage.
Perhaps tired of being victimized by Gonzalez's outer-half prowess, pitchers have busted him inside much more this year. That's especially the case with fastballs. Gonzalez hasn't been able to adjust to all the inside heat so far, and his power numbers are suffering.
Check out pitchers' fastball location versus Gonzalez in 2011, and then this season:
Opponents threw inside fastballs to Gonzalez 33 percent of the time in 2011, but that has jumped up to 43 percent in 2012. That's the second-highest percentage of inside fastballs seen by a lefty batter this season, behind only Atlanta's Jason Heyward. And loud contact for Gonzalez against inside heat has been about as common as quiet nights in the Boston media. Here's his slugging percentage vs. inside fastballs last season, and in 2012:
Gonzalez slugged .531 against inside fastballs in 2011, about 90 points above the MLB average. That has been cut in half in 2012. He's got one of the 20 lowest slugging percentages against inside heat this year:
Lowest slugging percentage vs. inside fastballs, 2012
Gonzalez's woes against inside fastballs go a long way toward explaining his 2012 power outage (he's slugging just .417 this season, compared to .548 during his first year with the Red Sox). Pitchers have adjusted their game plan against him, preferring to tie him up inside instead of watch him lace outside pitches off the Green Monster. Now, it's up to Gonzalez to counter-punch.