Another year, another season of Jeremy Guthrie having a better than average BABIP against and an ERA that beat his FIP/xFIP. I had projected him for 180 IP and a 4.15 ERA, but Guthrie posted his third straight 200+ innings pitched season (208) while failing to beat his peripherals by as much as usual (4.33 ERA, 4.48 FIP, 4.47 xFIP). His 2.1 fWAR placed him second on the pitching staff (behind Zach Britton's 2.5 - in over 50 fewer innings pitched), as he continued his run as a solid middle-of-the-rotation type starter (four out of five years in Baltimore he's had an fWAR between 2.1 and 2.6).
Early in the season I looked at Guthrie's tendency to post low BABIPs, saying that if we regress his career numbers than our estimate of his true talent BABIP is about .285. Actual 2011 BABIP against; .284. Normally that would have given him an ERA closer to 4, but Guthrie stranded runners a the worst rate of his career (only 69.6% left on base rate - about where the O's were as a team (the second lowest in the majors) - compared to 73% career).
On the bright side, Jeremy struck out batters at his highest rate since 2008 (a still below average 5.7 K/9). The curveball became a more prominent pitch for him, apparently at the expense of the slider (he threw breaking-balls about 26-27% of the time in both 2010 and 2011, but the mix was closer to even in the latter year - though still favoring the slider). This "resulted"* in both offerings inducing more whiffs, even if they're still not that great at getting swings and misses by normal standards. Most of increase in curveball usage came against left-handed batters**, who actually started to see the pitch more often than the slider.
* Not saying it's causal, but mixing the two pitches better - with the 10 mph difference between them - could conceivably make them both more effective.
** Not sure if I've noticed this before or not, but Guthrie has pretty small platoon splits for his career (and reverse ones in 2011); 4.53 xFIP versus righties, 4.69 xFIP versus lefites. And he's struck out left-handed batters more often (6 K/9 to 5.1 K/9)!
PitchFX also has Guthrie starting to use a cutter this past season. That might be part of the reason why his BABIP was above his career rate though, as fastballs from 2008-2010 with less horizontal tailing movement (like cutters) resulted in higher BABIPs while fastballs with more horizontal movement had BABIPs close to .250. Guthrie also threw fewer fastballs that had a lot of rise or a lot of sink (those pitches for 2008-2010 which had lower BABIPs) and was more consistent with his vertical movement (the in-between fastballs had the higher BABIPs).
Indeed, his BABIP on all fastball types (around .282) was a fair bit higher than it had been over the past few years (around .261). For the pitches categorized as regular fastballs, the BABIP was around .277; for the two-seamers (or "sinkers") it was around .221; and for the cutters it was around .267. One would think that would support the previous findings, but looking just at movement for all fastballs it was the ones with medium tail and medium sink that had the lowest BABIPs (though we're getting into some pretty small sample sizes at this point - and where the cut-offs for the different movement "buckets" are makes some difference). The mystery's still there, but it is interesting that the change in overall BABIP one would expect from the change in fastball types is actually what transpired (for change-ups the BABIP was up a bit too, but for the breaking-balls it was right on target).
Beyond the extra hits on balls in play, Guthrie also ended up walking the most batters he ever had; 2.9 BB/9. Much of that increase came against right-handed batter (he walked lefties at about his career rate of 3.1 BB/9). There might have been a bit of bad luck there, since it appears he threw pitches close to the zone more consistently but rarely seemed to get the pitch just down or just off the plate away called for a strike. In any case, 2.9 BB/9 isn't much higher than his career 2.7 BB/9.
With Jeremy Guthrie entering his final year of arbitration, it's possible the Orioles are going to shop him this off-season. There's a fair chance there's a team (or five) in need of a decent #3-4 starter who can provide some innings, and the O's can turn a 32 year-old into maybe a couple quality 22 year-old prospects. That would leave the 2012 rotation without it's rock (since he came over in 2007, Guthrie has started almost as many games for the team as the next three pitchers - D-Cab, Bergesen, Matusz - combined), but would probably be the best thing for the organization long-term.