The Brewers aren’t sure that they want to go to three years for Ryan Dempster, but they do need a pitcher now that Sean Marcum is seeing other teams. There are good reasons to like him — a few changes he’s made in his approach have seem to stuck — and there is one main reason to worry about giving him too many years.
From 2009 to 2012, Dempster has had an 8.5% walk rate, which is pretty much average. That average walk rate has made him an above-average starter, because he can get whiffs and usually has an average ground-ball rate. But in the first ten years of his career, he had a 11.1% unintentional walk rate. The peripheral best associated with walk rate is first strike percentage. In his first ten years, Dempster was better than average in that category only once — in his last four years he has not been below average once.
So that’s a change that has been good to Dempster, and looks sustainable. Dempster has also stayed true to himself over the years, and that may be concerning to teams looking at him for a multi-year deal.
Ryan Dempster has thrown the fifth-most sliders in baseball since 2009. He’s basically thrown the slide piece a third of the time over his entire career. Even as his pitching mix has changed around the pitch — maybe he’s thrown more cutters and splitters and fewer changes, or maybe the classifications have changed — he’s featured the slider as his best secondary pitch. The pitch has remained effective, counting as a negative only twice in his eleven-year career, and it’s certainly led to his above-average swinging strike and strikeout rates over the years.
But Dempster is going to be 36 next season, and that’s a lot of sliders on his arm. The work isn’t perfect, but there seems to be some evidence that sliders can be tough on arms and lead to more injuries. Last year he strained his shoulder — the first time he missed significant time with an arm/shoulder thing since Tommy John surgery in 2004, but still an injury.
The Brewers are rumored to be balking at adding a third year to the deal, and it might be for good reason. The Angels were once in on Dempster, but with the pitcher looking for three years, their interest has waned.
The thing that has changed — Dempster’s first-strike approach — bodes well for Dempster to keep up his newly found league-average control. But it’s the thing that has remained the same — Dempster’s reliance on the slider — that may make his age a big deal.