Pitching Mechanics Analysis
Chris Carpenter

Chris Carpenter has achieved ridiculous levels of success, but he's also had a problem staying healthy. His health problems are due to his pitching mechanics and, in particular, to a problem with a borderline Inverted L.

Chris Carpenter
2009
Continuous

At a glance, Chris Carpenter's pitching mechanics look solid and his delivery looks smooth and effortless.

Chris Carpenter
2009
Stop Frame

However, if you go through Chris Carpenter's delivery frame by frame, you can see a problem in his arm action and how it creates a subtle timing problem. The thing to notice in the clip above is how Chris Carpenter's Pitching Arm Side (PAS) forearm is horizontal, and not closer to vertical, in Frame 88 when his front foot plants and his shoulders start to rotate. As a result, Chris Carpenter's PAS upper arm externally rotates especially hard and much, increasing the load on both his elbow and his shoulder.

Chris Carpenter
120 Frames Per Second
September 7, 2011
Continuous

You can see the same pattern in these clips from late 2011.

Chris Carpenter
120 Frames Per Second
September 7, 2011
Stop Frame

Again, notice how Chris Carpenter leads with his PAS elbow out of his hand break. That causes his PAS elbow to get higher than is typical. As a result, his arm is late at the moment that his front foot plants and his shoulders start to rotate.

Notes

It may just be a coincidence, but Chris Carpenter's timing looks worse when he's going from the Set position than when he goes from the Wind-Up. However, it can happen that, in an effort to get to the plate faster and keep runners from being able to steal, a pitcher can hurt their timing. In other words, they may improve their ability to hold runners but hurt their timing (and increase their tendency to leave the ball up in the strike zone as a result).