A few days ago, I looked into Jay Bruce’s decline in power since his wrist injury last season. I asked our readers if there were any other players they wanted examined. Troy Tulowitzki, Derrek Lee, Jordan Schafer and Rickie Weeks were brought up. I don’t have the batted ball data around when Derrek Lee’s injury happened and Jordan Schafer was sent to AAA after coming off the DL, so neither of those two will be examined. That leaves Rickie Weeks and Troy Tulowitzki to be looked at closer.
I will be looking at the average distance in feet for the fly balls and line drives and the average angle they were hit towards (positive angle is to left field and negative number is to right field). The angle is important to look at because it shows that the batter is able to get the bat through the ball and drive it.
Rickie is a nice test case since he has broken his wrist twice since making to the big leagues: once in May 2007 and the other time in May 2009. Here is a look at line drive and fly ball distances and angles for Rickie from 2007 to current:
I am not for sure what to make of the data exactly. Before either injury, he was driving the ball to left field and averaging 277 ft per hit. After the first injury, he never hit for the same power in distance and started hitting the ball more towards center field. This season, it looks like he has had a boost of power and is starting to turn on the ball a little more. I am wondering if his 2007 injury never actually healed until this past off season.
Also, I divided this year’s data into two time frames. It can even be seen that he is increasing his distance over this season. Again, the one year recovery on wrist injuries looks to hold true.
Note: As asked in my last article, someone pointed out that the weather may be a concern (flyballs travel further in warm weather vice cold weather). The difference is that the ball travels at most ~3 less feet in April compared to a peak distance in June.
There is not much data since Troy’s return, but here is his data from the last 4 years:
Two pieces of information stick out to me right away, though.
First in 2008, he had much less power than in 2007 and 2009. Looking back to 2008, he had both a quadricep and hand injury during that season that may have slowed him down. I may also have to look if hand injuries have the same loss of power that wrist injuries do.
For 2010, he has hit for distance just fine, but before and after the injury, he was taking it more to center than he did previously. Since Troy has returned, he is hitting it even more towards center.
I am really needing to get some good baseline data to work off of for future analysis. I will probably wait to start it this off season so I can use all of the 2010 data on injuries and batted ball data.
Jeff, one of the authors of the fantasy baseball guide,The Process, writes for RotoGraphs, The Hardball Times, Rotowire, Baseball America, and BaseballHQ. He has been nominated for two SABR Analytics Research Award for Contemporary Analysis and won it in 2013 in tandem with Bill Petti. He has won three FSWA Awards including on for his MASH series. In his first two seasons in Tout Wars, he's won the H2H league and mixed auction league. Follow him on Twitter @jeffwzimmerman.