Between 2006 and 2009, the first four seasons that he was more or less a full-time player, Toronto Blue Jays outfielder Jose Bautista hit 59 home runs. In 2010, he came within five home runs of duplicating that total in a single season. Where did that power come from? A cursory look at his 2009 season, the one that preceded his incredible power breakout, seems to show no indication. In fact, his 13 home runs that season were his fewest in a season of his previous four. However, when you examine his first- and second-half splits in 2009, Bautista did show a discernible skill improvement that foreshadowed his massive 2010 season.
Bautista hit most of his 2009 home runs in a bunch over the last month or so of the season. That, in and of itself, is not a clear indicator of imminent home run dominance. For example, Domonic Brown of the Phillies hit 18 home runs between May and June of last season and only has seven home runs in the five months since. Moreover, Bautista actually declined slightly in his average fly ball distance from the first half of 2009 to the second half, which seems to suggest that his odd home runs split was just a fluke.
The evidence that Bautista's second half home run split was a real sign of things to come was in his average hang times. In the first half, his fly balls remained airborne for 4.31 seconds. In the second half, his average hang time jumped to more than five seconds, where it remained (5.08 seconds) in his 54-home run 2010 season.
Average fly ball hang times are useful because they accumulate a meaningful sample size much more quickly than home runs. The 200 or fewer plate appearances that most of the plate appearance leaders have accumulated so far in 2014 can create some anomalous home run totals because of ballpark dimensions and other factors, so let's look at players who have shown a marked increase in their average fly ball hang times compared to last year to predict which players with improved power numbers can expect that trend to continue and which players with disappointing power numbers can expect a turnaround as 2014 progresses.