Is Chase Headley’s Breakout Sustainable?

Chase Headley may have churned out the most surprising performance in baseball last season. While Headley was regarded as a decent third baseman in past seasons, he provided little power at his position. That changed drastically in 2012. Headley mashed 31 home runs despite playing half his games in a stadium that severely limits power. There were rumors that the San Diego Padres could make Headley available during the offseason, but the team vehemently denied they would entertain the possibility. With the team re-signing veterans Carlos Quentin and Huston Street, they seem to think they can compete for the division relatively soon. In order to do that, they’ll need Headley to sustain his offensive gains.

Prior to his breakout, Headley wasn’t much of an offensive threat. From 2008 to 2011, he hit .269/.342/.393 witha .326 wOBA. That’s passable at third, but hardly elite. That’s why what he managed to do last year was such a shock. Aside from the home runs, Headley’s slash line improved quite a bit, and he posted a .378 wOBA. In just one season, Headley’s wOBA jumped by.052, a staggering rate. In order to figure out whether the improvement is sustainable, we need to see if similar players have ever produced a similar jump.

On order to determine this, we can sort for players who had similar skills through the same age as Headley. In order to determine whether any of those players experienced a similar breakout to Headley, I created a custom list and looked at their performances during their age-28 season. When comparing each players wOBA, it turns out that similar players have experienced this type of breakout before, but few have improved as much as Headley.

Player	Age 24-27 wOBA	Age 28 wOBA	Dif
Charles Johnson	0.316	0.407	0.091
Todd Hundley	0.339	0.396	0.057
Chase Headley	0.326	0.378	0.052
Larry Hisle	0.351	0.390	0.039
Richie Sexson	0.364	0.393	0.029
Andruw Jones	0.355	0.383	0.028
Eric Hinske	0.333	0.360	0.027
Ricky Ledee	0.314	0.337	0.023
Dan Pasqua	0.343	0.365	0.022
Jay Buhner	0.357	0.374	0.017
Jose Bautista	0.323	0.338	0.015
Greg Vaughn	0.342	0.353	0.011
Alex Gordon	0.349	0.357	0.008
Tony Clark	0.369	0.372	0.003
Paul Sorrento	0.340	0.343	0.003
Phil Plantier	0.332	0.335	0.003

Of the 32 players included in the second link posted above, exactly half managed to improve their wOBA during their age-28 season, which is shown in the table. As the table shows, only two other players managed a bigger wOBA improvement than Headley, Charles Johnson and Todd Hundley.

Neither Hundley or Johnson were able to sustain their offensive breakout the following season.

Player	Age-28 wOBA	Age-29 wOBA	Dif
Chase Headley	0.378	N/A	?
Jose Bautista	0.338	0.422	0.084
Jay Buhner	0.374	0.400	0.026
Paul Sorrento	0.343	0.359	0.016
Ricky Ledee	0.337	0.343	0.006
Dan Pasqua	0.365	0.367	0.002
Andruw Jones	0.383	0.375	-0.008
Richie Sexson	0.393	0.383	-0.01
Tony Clark	0.372	0.362	-0.01
Greg Vaughn	0.353	0.320	-0.033
Eric Hinske	0.360	0.313	-0.047
Larry Hisle	0.390	0.335	-0.055
Charles Johnson	0.407	0.330	-0.077
Todd Hundley	0.396	0.246	-0.15

In fact, both players actually experienced the biggest wOBA declines the following season. In Johnson’s case, he regressed back to his career average. With Hundley, a catastrophic elbow injury derailed his season, and nearly his career. Even the players just below Headley on the first chart saw some pretty big regression on the second chart. You’ll notice that some guys that saw a decent rise in production on the first chart actually maintained or improved on their gains, like Jay Buhner, Andruw Jones and Richie Sexson, but all of those players gradually improved their wOBA, and didn’t experience a huge gain like Headley. The second chart also shows the breakout of Jose Bautista, which was sustainable, but due to a complete change in approach. That’s not necessarily something we have with Headley, outside of the newfound power.

When a player breaks out at a massive rate, like Headley, they are often not able to sustain those gains the following season. Most players that are able to improve, or sustain their performances, typically experience a less extreme improvement, like Sexson and Jones. This doesn’t necessarily mean that Headley is doomed to revert back to the guy who posted a .326 wOBA over four straight years, but it does mean that he’s probably in for some serious regression.