Nick Carfardo's recent Boston Globe article "It's all in place" focuses on the history of left-handed hitters benefiting (or not benefiting) from Fenway Park's dimensions. Much of the article centers on how Adrian Gonzalez will fit in and whether he can use the left field wall to his advantage, as did many successful left-handed Red Sox batters before him.
A while back, David Pinto noted in a post how Adrian Gonzalez can hit for power to all fields. Petco park most definitely suppressed his offense, unsurprisingly, as it is one of the best pitching parks in the league. At Fenway, Gonzalez should see a decent boost in his power numbers. In Cafardo's article, he notes that pitcher's will likely try to bust Gonzalez in this year at home in order to limit his use of the wall in left. Gonzalez's response: "They’ve been doing that to me for years anyway. I’ve always been able to inside-out it the other way.’’
On pitches inside (anything from the inside 3.5" of the plate and in) Gonzalez has actually hit very few balls to left field. In fact, since 2008, he's hit no HRs to left, one HR to left center, and 19 HRs to right or right center on pitches inside.
(Click to enlarge)
In the 689 plate appearances represented in the graphic above, Gonzalez produced a .740 OPS on 154 hits, with 29 doubles and 20 HRs. However, all but 8 of those extra base hits fell right of dead center field. His 105 singles over that period were fairly spread out across all fields, however the majority fell in what would be well short of the wall in left, as did his 119 fly ball outs.
Of course, Gonzalez will be successful regardless of whether or not he's banging balls off the wall in left. Even if pitcher's come in on him, a .740 OPS over the past 3 years is nothing to scoff at. Considering that Gonzalez's expected OBP on pitches inside since 2008 is .388, he's likely to be successful even if pitchers try to jam him.