New York Yankees center fielder Curtis Granderson is crushing fastballs this season. His .785 slugging percentage against them ranks first in the league, as does his 1.231 OPS. Also, 11.5% of his at bats decided on a fastball have resulted in a home run.
Considering how he's done versus fastballs in the past two years, his current season has been quite an improvement.
What has helped Granderson's overall numbers against fastballs has been his ability to lay off pitches out of the zone. In 2010, he chased 26.6% of fastballs out of the zone, and 23.5% in 2009. This season, he's chasing only 18.5%.
You can see from the above graphic that Granderson is swinging at more fastballs that land in the zone, while chasing outside fastballs a bit less. His increased plate discipline has resulted in a lot more production. And while his 34 total HRs is second behind Jose Bautista's 35, his 23 HRs off fastballs leads all major leaguers.