When we see a hitter significantly raise his batting average, we often see one very common trait: he's using the whole field more. This is not the case with the recent emergence of Bryce Harper.
Harper was a .273 hitter over his first 357 games, 2012-2014. In 2015 he's batting .336 with a significantly larger bump in OBP (.474).
And Harper's not sacrificing power for the higher batting average. Harper's 9.13 HR/AB rate is better than double that of his first three seasons.
Home runs are up, batting average is up, and he's pulling the ball more. Those three things usually don't go together, especially the pull part. Check out Harper's contact percentages on where balls were put in play over his career.
| Year | Pull% | Center% | Oppo% |
| 2012 | 32% | 38% | 31% |
| 2013 | 40% | 37% | 23% |
| 2014 | 40% | 35% | 26% |
| 2015 | 51% | 32% | 18% |
I talked to Matt Williams a couple of weeks ago and he raved about Harper's growth. He told me that Harper has become more disciplined at the plate without giving up any aggressiveness. He knows what he's looking for and he's willing to wait longer for it than before.
| Year | O-Swing% | Z-Swing% | Swing% |
| 2012 | 35% | 75% | 50% |
| 2013 | 34% | 75% | 49% |
| 2014 | 36% | 76% | 51% |
| 2015 | 29% | 70% | 45% |
(O = swings outside the zone, Z = swings inside the zone, Swing = total swings)
This PITCHf/x swing data backs up William's explanation. Harper is swinging less. He is swinging at fewer pitches both in and out of the strike zone, but when he does swing he's making it count.
Harper has figured it out. It was never about toning down the aggressiveness, it was about building up a mental database through experience and being confident enough to be more selective.
