Every year a dozen or so MLB pitchers need to have TJS (Tommy John surgery) done on their elbows. Today I will look at 3 of those pitchers (Joe Nathan, Jordan Zimmermann and Edinson Volquez) that had the surgery in 2009 or 2010 with 2011 being their first full season back. Also, I will look at some general TJS information and how it applies to the 3 pitchers.
General Rules of Thumb on TJS
I am been trying to get a good data set of information on TJS and am currently in the middle of collecting that data. I have a list of 350 pitchers that have had the surgery performed on them at least once. Hopefully sometime before the end of the season, I can get all the information available.
I do have a couple of rules of thumb I use when dealing with pitchers returning from the surgery.
1. Most pitchers regain their velocity seen a year or two prior to the operation. Don’t look at the year that the injury happen as it is probably down. Go back a year. Sometimes they lose velocity coming back, but rarely gain from their all time high.
2. It takes a year for a pitcher throwing in the majors to get back to where they were previously performing. Some return to their previous form faster, others take a little longer, if at all.
Here is a quick look at 3 pitchers that returned to pitching full time this season and their results.
Edinson Volquez – Edison has been in the news recently for being demoted for saying that his team has not been scoring enough runs for him. Enough has been said of his off the field antics, here is what he has done on the field over the past 4 seasons:
Edison’s fastball is back to pre-injury levels and his strikeout rate has followed. His main problem has been the walks which have increased since the surgery. No pitcher is going to make it in the majors giving up close to 7 walks per 9 innings. Physically it seems that Edison is fine. He now just needs to get his head screwed on correctly.
Joe Nathan – Joe has already lost his closer role with the Twins because he was ineffective. Looking at his numbers you can see why:
Fastball velocity down 2 MPH. SwgStr% cut in half. Walk rate has doubled. In my opinion, I think he was rushed back too soon. There was much discussion in Spring Training on if he was going to pitch or not. He might have needed to wait to build up his arm strength. One thing I have noticed is that his fastball is slowly gaining speed and it may eventually get up to its previous levels. Maybe.
Jordan Zimmermann – With Strasburg out with TJS, Jordan was to take his place as the staff’s ace for this season. He has not performed to bad so far this year compared to his previous major league season:
His fastball velocity and walk rate are similar to pre-surgery levels. His main problem is that his swinging strike and K/9 rate are down. As Zach Sanders notes, he has seen improvement over the last month in his K rate.
All three of these pitchers are back pitching, but aren’t back completely to their pre-injury levels. I would expect some more improvement from each as the season goes on.
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.