Thursday, October 01, 2009
Corey Hart finished for season; did plate discipline impact his power?Posted by Evan Brunell
Corey Hart's season is over after x-rays showed possible compression fractures in his right hand, stemming from his fourth and fifth fingers. Bone scans will later confirm the story, but there's no way Hart returns to the ballfield in 2009.
As a result, the right-fielder finishes his season with a .260/.335/.418 line, disappointing in the power field given he had knocked out 20 and 24 home runs, respectively, the two previous seasons. This year, in roughly 100-200 less plate appearances than 2007-8, he finished with just 12 in 472 PAs.
While the power sapping could partly be attributed to the emergency appendectomy that knocked him out for a stretch of time earlier this year, manager Ken Macha has other ideas.
“We were trying to get him more disciplined at the plate and not swing at sliders out of the zone, and we accomplished that,” Macha told the Milwaukee Journal-Sentinel. “But we took away a little bit of the aggressiveness, maybe sapped him of his power."
There's no question he boosted his plate discipline -- simple numbers bear that out. Here are his walk percentages since 2006, when he began amassing significant at-bats.
6.7, 6.7 (there's something to be said for consistency), 4.2, 9.3.
Taking a glance at ratios that bely power numbers, let's check line drive percentages out across the same time period: 16.7, 17.1, 19.2, 17.2.
One more; home runs per fly ball percentage: 12.2, 13, 9.9, 8.8.
While there may appear to be a correlation between his low walk total and line drive percentage, his best power season came in 2007 when he posted near identical line drive numbers while juicing balls out of the park at a better clip. He's hit additional ground balls on the year percentage-wise than fly balls, but that's generally a moot point when you're talking a difference between a ground ball and a fly ball -- ground balls aren't going to go out of the park and likely shouldn't be considered.
The additional ground balls may be a factor in his weakness from appendectomy or a mechanical flaw, but to say that improving his plate discipline has "sapped" his power is shaky logic. I don't pretend to have answers, but I do know that I don't agree with Macha.
Evan Brunell is currently editor of Fire Brand of the American League, a Red Sox blog he began in 2003. He also scores games at Fenway Park for MLB. He was the co-founder and president of MVN, an independent sports media web site.