With Ron Gardenhire stating in an interview today that Brian Duensing will "absolutely" be in the Twins starting rotation, and assuming that Francisco Liriano and Carl Pavano are also assured spots, 3 starting pitchers are vying for the final 2 spots in the rotation...the music is still playing, but this game of musical chairs only has about a month to play itself out. I know that Gardenhire could very well change his mind between now and Opening Day, and an injury (or, *gasp*, a trade) could occur, but based on what we know now, I thought I would play manager for a minute and break down the 3 remaining pitchers to see who I would choose.
For each of the last 3 seasons, Baker has given the Twins at least 28 starts and at least 170 innings. With a 38-22 record over that time (i know, wins don't mean much) he's proven himself a competent starting pitcher and most teams would be lucky to have him in a 4th or 5th starting pitcher role.
It's a little hard to gauge the end of last season for Baker because he was having some elbow tendinitis. In his last two starts of the year, he pitched 5 innings in both game, and struck out 16. What has been somewhat frustrating over the course of Baker's career is that he can go from looking like in ace in one start, to a rookie in the next. This was highlighted perfectly by two starts Baker made in the middle of the season last year. On June 16th, Baker faced the Rockies at home and threw 7 innings of 2-hit ball, striking out 12 and walking just 1. In his very next start at Milwaukee, he got shelled for 5 earned runs and walked 5 in 6 innings (he also gave up 5 runs against KC in his start prior to the Colorado game). This roller-coaster ride is frustrating to no end and it's a strike against Baker in terms of his consideration for the starting rotation. Fortunately for him, his competition has similar problems.
In terms of WAR and WPA (Win Probability Added), 2010 was Baker's poorest showing in both categories and in fact, his WPA has declined in each of the last three seasons to the point where he was only very slightly above average last year. His inability to make his best pitches (fastball and slider) work for him is most certainly the culprit, as evidenced by the graph below.
As you can see, Baker's slider has been his most valuable pitch over the course of his career (see here for Pitch Type Values explanation). In 2008, that pitch was worth 10.4 runs, but it declined to -0.3 runs in 2009 and 2.4 runs in 2010. In 2009, his fastball was 21.9 runs which carried him through, but that fell to -8.9 runs in 2010 and with his slider only being slightly above average last year, his overall results were fairly mediocre. The predictive value of these statistics is pretty limited, but it's fair to say that Baker needs to concentrate on either his slider or his fastball and have at least one effective weapon in order to make him truly effective as a pitcher. We've all seen that he has "stuff" (near no-hitter anyone?), he just needs to be more consistent with it, whether "it" is the slider or the fastball.
Since 2008 when Slowey started 27 games for the Twins and pitched to a 3.99 ERA, it's been a rough ride. In 2009, his season was cut short by a wrist injury (missed most of July and all of August and September) and in 2010, he started 28 games, but was hampered toward the end of the season with triceps issues. Even despite all of that, he still makes an intriguing option in the 4th of 5th slot of a rotation and he sports the type of thing the Twins coaching staff loves...pitch control.
What Slowey and Baker share in common is that they are both flyball pitchers. This seems to be less of a issue in the new ballpark, but it tends to lead to higher ERAs on paper. Slowey's 2010 season qualified him as an extreme flyball pitcher due to the fact that over 50% of the balls hit in play against him were of the flyball variety (as opposed to only 28.3% groundballs). Since 2007, only 3 pitchers in all of baseball have induced flyballs at a higher rate than Slowey: Chris Young, Oliver Perez and Ted Lilly. Scott Baker is 10th on that list. What makes Kevin effective is his ability to command his pitches and over that same period of time Slowey is 2nd to only Roy Halladay in K/BB ratio at 4.60.
I'm not going to highlight any charts when talking about Slowey, but suffice to say he's been a VERY average pitcher during his career to this point. I could go on a rant about how Slowey is the very definition of the type of pitcher the Twins organization seems to love and how he's a poster boy for "average pitcher," but I'll stop. Slowey is a pitch-to-contact pitcher and I can't see his being all that much better than he has already shown. His zone contact percentage (% of time a hitter makes contact on a pitch thrown in the strikezone) was 90.2% last season and it sits at 88.6% for his career. Without the ability to miss bats, a pitcher's ceiling only goes so high, particularly when they are as extreme a flyball pitcher as Slowey is.
To say that Blackburn had a rough 2010 season would be to put it lightly. He started the year in the starting rotation, had a terrible April and May and an absolutely brutal June and July, got demoted to Triple-A and then rejoined the starting rotation when Baker and Slowey went through their injury troubles. To his credit, he was actually mostly effective in his final 8 starts of the year (except for a 9/28 start when he gave up 8ERs to the Royals), and seemed to find something of what he had been missing prior to his demotion.
Unlike Baker and Slowey, Blackburn's success comes when he is keeping the ball down and inducing groundballs. If he can't keep the ball down, he gets shelled because his fastball doesn't fool anyone (only 3.9 K/9 in 2010). Now you might say, "but Blackburn induced groundballs at a career-best 50.8% last year!" And you'd be right. Where he struggled was in the strikeout and walks department, namely, he gave up more walks and struck out even fewer batters than normal. I could go through it all, but David Golebiewski over at FanGraphs did that for me last year. In case you don't feel like reading it, or it makes you sick to your stomach to read about Blackie's struggles last year, the main premise of the piece is that Blackburn struggled last year due to his inability to get hitters to swing at marginal pitches. Because Blackie wasn't missing bats, and because he was unable to throw many strikes with his secondary pitches (cutter, curve, change) he walked more guys and for a guy who strikes out as few as he does, even a small change in the results he's getting from his pitches can equal a drastic difference in his numbers.
Getting back to the final 8 starts of last season, Blackburn only gave up 13 walks in his final 57 innings pitched while striking out 33. This allowed him to regain some effectiveness and the overall results of those 8 starts were much better than the previous 18...which all brings me back to the question of whether he should be in the rotation. I simply don't know, only the Spring (and Rick Anderson/Ron Gardenhire) will tell.
So that's the analysis. I guess if I had to say who I would choose, it would come down to Scott Baker and Kevin Slowey. One other thing to consider is, would Blackburn be an effective pitcher out of the bullpen? If the answer to that question is no, then you're kind stuck having to throw him in there. The Twins can't just demote him to Triple-A because for some unknown reason they decided to give the guy a $14M contract prior to last season. I think Blackburn will be a more effective pitcher than he was in 2010, but I just can't say for sure. If he can't be effective out of the 'pen though, I think you have to make him the 5th starter and put Slowey in the pen. I've seen too many flashes of greatness from Baker and he definitely has the most upside out of the bunch, so I want him in the rotation. I could further complicate things by reminding everyone that Kyle Gibson is sitting there waiting for his chance as well...who's he gonna replace? Or will he be a bullpen player as well? Should be an interesting season in the starting rotation category.