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Position Battles: M’s Bullpen

The Seattle Mariners enter spring training with a wide-open situation in the bullpen. The M’s will no longer give the ball to J.J. Putz in the ninth inning, as the soon-to-be 32 year-old was shipped to the Mets in a twelve-player package. Also headed to Queens in that swap was groundball specialist Sean Green. After two years of, well, putsing around in the ‘pen, 2006 first-rounder Brandon Morrow will be moved to the rotation on a full-time basis. So, who’s left in that Seattle bullpen? Let’s take a look.

The top returning reliever, per WPA, is righty Roy Corcoran. The smallish 28 year-old turned in a 3.81 FIP and kept his infielders very busy (69.5 GB%), but there’s some question about the repeatability of his work. The former Expo/Nat struck out about as many batters (4.83 K/9) as he walked (4.46 BB/9) and his career minor league walk rate (4.14 BB/9) is rather high as well. Low-K pitchers can be plenty successful by inducing grounders and limiting walks, but Corcoran doesn’t appear to have the control to make that equation work.

Mark Lowe, 28, is coming off of a season in which he posted a 4.42 FIP. He punched out 7.77 batters per nine innings, but his control often evaded him (4.81 BB/9). The 6-3, 200 pounder has long been on prospect lists due to his mid-90’s heat/mid-80’s slider combo, but injuries (shoulder impingement as well as microfracture surgery on his elbow in an effort to regenerate cartilage in the joint) have held him back. If you’re looking for a guy who fits the closer profile from a “stuff” standpoint, it’s probably Lowe.

Like Lowe, David Aardsma is a flame-throwing righty without sharp command. The 27 year-old’s mix of mid-90’s fastballs and hard sliders have yet to produce anything but angst for his employers, as Aardsma has skipped between the Giants, Cubs, White Sox and Red Sox, before ending up in Seattle for minor league southpaw Fabian Williamson. The 2003 first-rounder has fanned his fair share of hitters in the bigs (8.65 K/9), but an atrocious walk rate (5.6 BB/9) has kept him from being anything more than a replacement-level reliever, with a 4.90 FIP. One thing to watch: according to our pitch data, Aardsma started using an upper-80’s splitter (thrown 10.9% of the time) in addition to his fastball and slider. The chances of Aardsma finally delivering are long, but the M’s have some experience with a control-challenged reliever adding a splitter and subsequently taking off.

Tyler Walker, formerly of the Giants, might also be able to work his way into the mix. The 32 year-old posted a 4.24 FIP last season, with 8.27 K/9 and 3.54 BB/9. The 6-3, 275 pounder works in the low 90’s with his fastball, but has progressivley become more reliant on a low 80’s slider (thrown 30% in ’06, 31.4% in ’07 and 40.3% in ’08).

It’s also possible that some of the team’s rotation excess ends up in the ‘pen, particularly lefties Ryan Rowland-Smith and Ryan Feierabend. Rowland-Smith appeared in 47 games last season (12 starts), posting a 4.53 FIP. His fastball won’t overwhelm anyone (88.7 MPH), but he also mixes in a slider, curve and a changeup on a fairly regular basis. Similarly, Feierabend supplements modest heat (87.8 MPH) with three offspeed pitches, relying heavily upon a high-70’s changeup.

Another long-term name to keep in mind is Josh Fields. The former Georgia Bulldog closer was selected by the Braves in the ’07 amateur draft, but the club didn’t meet his bonus demands. After improving his stock during the 2008 season, Fields was nabbed by the M’s with the 20th overall pick and…didn’t sign, at least not right away. The Boras client recently came to terms, however, receiving a bonus nearing $2 million (as a college senior, Fields had up until next June’s draft to negotiate a contract). The 23 year-old righty fits the profile of a late-inning reliever better than any of the current options, as he comes equipped with mid-90’s gas and a hard curveball. The 6-0, 180 pounder is likely the heir apparent to Putz in the long run.