Thursday, February 10, 2011

Six For Five

Six starting pitchers are showing up in training camp this year, and five will leave. I'm excited about the possibility of a little competition, partly because I'd like to see what Slowey can do when he needs to find a way to work with his catcher. Or how Baker reacts when he faces the possibility of being dropped from the rotation if he doesn't stay healthy through spring training.
It's been a while since I gave a lot of thought to last year's performance of the members of the starting rotation. So as a way of reintroducing myself to each of them, let's take a quick look at how each of them ranked in terms of some statistics. I'm really focusing on the four guys, Scott Baker, Nick Blackburn, Kevin Slowey and Brian Duensing, who are fighting for three spots.

Brian Duensing wins this one with a 3.05 ERA as a starter, better than anyone else, including Francisco Liriano(3.62) and Carl Pavano(3.75). Baker(4.49) and Slowey(4.54) are about even, and Blackburn(5.30) was quite a way behind them.

Quality Starts
I don't think I'm going to find a lot of areas where Blackburn isn't in last place, but I find it interesting that he led the "other four" pitchers in quality starts last year with 14. Baker had 12, and Slowey had nine. You could also award this category to Duensing, who had nine quality starts in just 13 starts, the highest percentage of quality starts on the staff.

Other than Liriano, Baker easily wins this category. He was second on the team in strikeouts(148) overall and in terms of strikeout rate(7.48). Slowey(6.78) is third in rate, Duensing(5.36) was fourth, Pavano(4.76) fifth, and Blackburn(3.76) last.

Eating Innings
Pavano was, by far(221 IP, 32 starts), the leader in this category. Liriano finished second in overall innings, but was actually third in innings per start (6.19 IP per start) behind Duensing(6.54). Blackburn ranked just below Liriano in innings per start (6.08). I'm surprised to find Slowey (5.95) ahead of Baker (5.86).

Oh, hell, let's throw one in for the sabrites out there. xFIP is something that looks like ERA but is derived from a pitcher's strikeouts, walks, and fly ball percentage. It is valuable because it is a better predictor of a starting pitcher's ERA than their ERA the previous year.

Liriano (3.06) and Pavano (4.01) led the team last year, but Baker (4.02) was a very close third. Duensing was also very close to those three with 4.10. Slowey (4.48) and Blackburn (4.62) were quite a bit behind the rest.

WHIP (Walks + Hits/Innings Pitched)
How good is each pitcher at keeping players off the base paths? Pavano was by far the best (1.19) but Liriano (1.26) just missed out on second place. That honor belongs to Duensing (1.25) who is putting together a pretty solid argument for being the third strongest pitcher on this staff by this point. Slowey (1.31) and Baker (1.34) are not too far behind. Blackburn (1.44) is again in last place.

Baker's got "the stuff", with Slowey a close second. Blackburn had some terrible stretches last year, but showed that even when he is terrible, he can eat innings and provide quality starts. But this analysis has really opened my eyes on the year Duensing had. He was among the leaders in ERA, quality starts, eating innings and WHIP. For two years now we've seen what he can do for a half year in the rotation. I think it might be time to see what he can do for a full year.


Seth's Minnesota Twins Prospect Handbook 2011 is now available online. To order today, click here.


TT said...

Just to be clear.

Strikeout rate is a ratio of outs a pitcher gets by strikeout, not how often they strike batters out.

xFIP is a bit of a black box with all sorts of 'adjustments'. But this " strikeouts, walks, and fly ball percentage" is almost certainly not accurate. Like FIP, it appears that xFIP is based in part on the number of outs a team gets while a pitcher is in the game. It doesn't matter whether those outs result from good fielding, inducing poorly hit balls or strikeouts.

The other problem with FIP (I don't know if this applies to xFIP) is the basic adjustment to get it to look like ERA. If you subtract the typical adjustment of 3.2 from those numbers here is what you get:

Liriano (.04)
Pavano (.81)
Baker (.82)
Duensing (.90)
Slowey (1.28)
Blackburn (1.42)

In other words, Blackburn's actual ratio is 35 times that of Liriano. Its hard to believe there is any ability where that much difference actually exists.

The term "eating innings" is a bit misleading. You are really measuring how many outs a pitcher got. Since that is the main objective of pitchers, we ought to consider it the most basic measure of a pitcher's effectiveness.

The real measure of "How good is each pitcher at keeping players off the base paths? " is IP per BFP. The weakness of WHIP for that purpose is that it undervalues pitchers who are effective at inducing double play ground balls.

I agree with the conclusion on Duensing. I think he actually has a leg up on Slowey and Blackburn in the competition for a spot in the rotation.

I think Baker would really have to look bad in spring training to lose his spot. With the other three, I think performance in spring training is going to make the decision. Last year's stats are mostly a tie-breaker, but I think Duensing wins in case of a tie.

Anonymous said...

SEIRA correlates with future ERA a little more strongly than FIP or XFIP and I think a better predictor than either of those two, although we're talking marginal gains. The relevant Twins starters from 2010...

Liriano - 3.02
Baker - 3.69
Slowey - 4.14
Pavano - 4.15
Duensing - 4.22
Blackburn - 4.83

Small signs, sure, but a little comforting to think that the beta version of the new PECOTA sees better things for Liriano, Baker Slowey and Blackburn in 2011, even if it pegs Pavano and Blackburn for a regression (but credit Smith, it's not like he caved and paid Pavano like he was a sub-four starter).