A Closer Look at Shaun Marcum’s Mechanics

The Brewers had their first official Shaun Marcum Injury Scare of the season this past week, when the right-hander was pulled early from a spring start due to shoulder stiffness. Luckily for the Brewers, it turned out to be nothing, and Marcum is only expected to miss a spring start. Unfortunately, this probably won’t be the last time we get a scare this season.

Marcum’s delivery has been a topic of discussion among Brewers bloggers since the day he got to Milwaukee, and while it is a concern, some of us preferred to look at the positives instead. With Marcum possibly missing some time, though, it’s probably worth taking another look.

If you aren’t all that familiar with pitching mechanics or want to know exactly why his delivery raises some red flags, I’ll try to break it down here the best I can, using screen grabs from a start against Baltimore last season.

If you want a simplistic explanation for Marcum’s history of arm and shoulder problems, they can probably be traced back to the dreaded “Inverted W” — when a pitcher’s elbows actually rise above his shoulders:


As Tom Verducci explained in a recent Sports Illustrated article on Stephen Strasburg‘s flawed mechanics, though, the problem isn’t so much with the Inverted W itself.

The problem is the timing associated with that move, not the move itself. When Strasburg gets his elbows above his shoulders and the baseball is below or about even with his right shoulder, his stride foot is hitting the ground. The ball should be in the loaded position at that point, but because Strasburg uses the funky “high elbow” raise, he still has to rotate his arm above his shoulder to get it there. The energy from landing on his stride foot has passed too early to the shoulder and elbow — before the joints are ready to use it.

The same applies to Marcum. Like Strasburg, Marcum’s plant foot is hitting the ground before his arm is “cocked” in an upright position. In the screen grab below, you can see how Marcum’s arm is lagging behind the rest of his body when his foot hits the ground.


The end result is more pressure than normal on the shoulder and elbow, due to the increased amount of torque necessary to get things up to speed. As you can see, by the time the ball is in the “loaded” position, Marcum’s body is almost square with the plate.


By the time Marcum’s torso is square with the plate — usually when a pitcher is starting his follow-through — Marcum’s arm is still lagging behind. At this point, there’s really no more momentum being provided by the body…it’s all on the arm. To me, this image does a good job of showing just how much pressure is being put on that surgically-repaired elbow (although you may need to watch the video to really see the arm torque).

Verducci quotes an anonymous front office “decision maker” that says his team won’t consider any pitcher whose arm is late when his foot hits the ground. Considering the Brewers have bought into biomechanics so heavily — even after dismissing Rick Peterson, they’re keeping his philosophies throughout the system — it could be considered a surprise that they traded for Marcum in the first place. Of course, that could possibly be traced back to Doug Melvin’s desperation to win this season. He’s willing to roll the dice on an injury risk if Marcum is able to win the team games the next two seasons. At least we can be sure Verducci’s anonymous source isn’t anyone in the Brewers’ camp.

Marcum is team property through next season, and his numbers suggest he’d be in line for a nice payday if he were to hit free agency. Toronto traded Marcum because they seemingly had no intentions of giving him a longterm deal, and wanted to capitalize on his value while he was healthy. Does that make it a bad trade for the Brewers? Of course not. It’s a move that carries a lot of risk considering Marcum’s history and mechanics, but there’s always the chance that it works out in their favor.

It’d be foolish to sit here and guarantee that Marcum will blow his arm out again as a member of the Brewers, but I will say this — expect a DL stint or two. While he was mostly healthy last year, Marcum still spent some time on the DL with elbow inflammation. Don’t be surprised if the same happens this year. Not every incidence of elbow inflammation or shoulder stiffness will be catastrophic, but the risk is going to be there all year long. The best the Brewers can do is take advantage of the time he is able to spend on the mound, and hope they’re set up to do well when he isn’t.