Cahill’s Tough Year

Coming into the season two members of the A’s youthful rotation were particularly exciting to watch. Trevor Cahill and Brett Anderson were both top prospects and linked by a host of similarities, both were just 21 years old to start the season, had never pitched above AA and had the rare combination of good ground ball and strikeout numbers. Both pitchers struck out over 8 batters per 9 innings and got over 50% ground balls per ball in play at every level in the minors coming into this year. The big difference is that Anderson combined those skills with excellent walk numbers, while Cahill’s were poor.

That difference as translated to the bigs. Anderson is having an amazing season. By FIP he is the 10th best starter in the AL, an amazing feat for someone of his age and experience. Dave C. and I have each profiled him already (here and here), so I will turn my attention to Cahill’s season.

His ground ball rate is solid (over 47%), but his walk (3.6 per 9) and strikeout (4.6 per 9) numbers have been bad. In fact his K/BB ratio is second worst (again to John Lannan) among qualifying starters. Here is the movement on his pitches.


Like many ground ball pitchers Cahill throws a lot of fastballs (almost 70% of the time), and the problem is he has not been very good at getting them in the zone. His fastballs are in the permissive pfx zone 50% of the time, compared to the 55% for the average fastball. This is one of those things that seems like a small difference but is not. The variation is fastball zone percentage is narrow, so 50% is quite low, and over the course of the whole year those extra balls really pile up.

Cahill has the stuff. His two-seam fastball induces lots of ground balls (55%) while getting an almost average whiff rate (13%) and his good changeup gives him a solid option against lefties. Although this has been a rough year he is very young and with improvement in his command he will be a solid pitcher.

Dave Allen's other baseball work can be found at Baseball Analysts.

Newest Most Voted
Inline Feedbacks
View all comments
14 years ago

K rates are overrated. Look at the bottom 10 in K rate and the top 10 K rate. There isn’t a huge difference in their performance. John Lannan is not terrible company to keep. Lannan, Piniero, Duke, Blackburn are not bad pitchers.

Not David
14 years ago
Reply to  pm

John Lannan, he of the ~5 FIP, in the NL?

Not the company I’d like to keep.

14 years ago
Reply to  Not David

His ERA has been consistently much lower than his FIP despite playing alongside terrible defensive teams. I think it’s likely that he is one of those pitchers who can be better than their FIP.

David Foy
14 years ago
Reply to  pm


Your premise that the bottom 10 in strikeouts are about equal in skill to the top 10 is startlingly false and shows that you failed to even look at the leader boards.

Top 10
Justin Verlander
Tim Lincecum
Zack Greinke
Javier Vazquez
Jon Lester
Dan Haren
Felix Hernandez
Yovani Gallardo
Josh Beckett
Adam Wainwright

Bottom 10
Jeff Suppan
John Lannan
Rick Porcello
Nick Blackburn
Trevor Cahill
Jamie Moyer
Randy Wells
Joe Saunders
Braden Looper
Zach Duke