David Laurila stated the following about the Doug Fister to the Nationals trade.
Have to believe Tigers know something about Fister the rest of us don’t. Dombrowski isn’t dumb.
— David Laurila (@DavidLaurilaQA) December 3, 2013
I responded to his tweet with any possible injury factors, but I wanted to go into more detail here. I examined as many factors I have seen with other injured pitchers (declining velocity) and I could only find two possible indicators, inconsistent release points and low Zone%. Both of them are relatively small and shouldn’t be a deterrent to trading for Fister.
First, he maintain an inconsistent release point between games and during a game compared to other pitchers. Here is his 2013 release point plot from Brookbaseball.net and Max Scherzer’s plot for comparison.
Inconsistent release can be the sign a pitcher struggling to find a repeatable delivery. With Fister, he had a similar release point pattern since he has been in the league. The Tigers didn’t trade him then because of it.
Somewhat in the same boat is his inability to find the strike zone at the end of the 2013 season. Here are his last six Zone%’s (47% is the sign of a possible injury):
He showed a little bit of wildness, but nothing a pitcher doesn’t go through sometimes. In all, I just don’t see any obvious signs of a injury.