One of the biggest difference we’ll see between the 2011 and 2012 versions of the Boston Red Sox is their revamped bullpen.  Ace reliever Jonathan Papelbon has taken his services to Philadelphia; fireballing set-up man Daniel Bard has been moved into the rotation; and the steady Dan Wheeler has signed a minor league deal with the Indians last week.  Over the past couple of months, Ben Cherington has gone to great lengths to rebuild the bullpen with talented, yet cheaper arms.  Through a few shrewd trades that sacrificed nothing more than surplus talent, he’s put together a solid group that has the potential of being extraordinarily effective if a few things break in their favor.  In preparation for the upcoming season (albeit a very early one), I thought I’d take a look at the projected construction of the 2012 bullpen.

Andrew Bailey (Closer) – I don’t think Bailey needs to be reminded he has some big shoes to fill.  His predecessor, Jonathan Papelbon, displayed long-term dominance that has rarely been seen by closers not named Mariano Rivera, Dennis Eckersley, or Goose Gossage.  During his six-plus year tenure in Boston, he racked up 15.1 fWAR, produced a 2.60 FIP, and mowed down nearly 30% of the batters he faced.   Bailey won’t be able to replicate Papelbon’s success, but then again, he doesn’t really need to as countless lesser pitchers have successfully encumbered the closer role over the years.

Bailey’s a pretty solid pitcher in his own right.  He has a three pitch repertoire that includes a four-seamer, cutter, and curve.  He has good command of all three, and can generate whiffs with the cutter and four-seamer.  Between 2009 and 2011, he had considerable success pitching out of the closer role for the A’s, producing a 2.74 FIP, striking out 25% of the batters he faced, and walking only 7%.  Due to his orientation toward fly balls, he was able to take advantage of the vast outfield and foul territory dimensions at the O.com Coliseum.  While he won’t be allowed that same luxury pitching half of his games at Fenway where foul territory is pretty scarce, this change shouldn’t be too much of a concern.  Bailey’s biggest hurdle will be avoiding the injury bug.  He’s only thrown 90-2/3 innings over the past two seasons, and has experienced elbow issues to boot.  If he can stay healthy, we could be looking at a solid 2-fWAR reliever finishing off our games.

Mark Melancon (Set-Up) – While he isn’t an ideal pitcher for the closer job, Melancon did an admirable job filling the role for the Houston Astros last season, producing a 3.24 FIP and saving 20 games in 74-1/3 innings.  Now with the Red Sox, he’ll be called upon by Bobby Valentine to fill the crucial, high leverage situations in the seventh and eighth innings that Daniel Bard used to lock down.  Based on his skill set alone, he appears to be more than capable of doing the job.  Melancon has a five pitch repertoire, but he primarily relies on his four-seamer, cutter, and curve to get hitters out.  Unlike most pitchers who throw a curveball; he not only induces a lot of swings (47%), but also generates a ton of whiffs (17.4%).  As a result, it’s a pretty effective weapon in his arsenal, especially when thrown to righties.  Last season, he exhibited a noticeable righty (2.64 FIP)/lefty (4.17) platoon split.  While his strikeout rate (21%) between the two groups remained static, his walk and HR/FB rates spiked against opposite-handed batters.  This isn’t terribly uncommon in the relief pitcher corps, but we can probably pin some of the “blame” on small sample size (particularly with his 23.1% HR/FB rate).  In the event of an injury to Bailey, Melancon will likely be the first option to soak up save opportunities.

Alfredo Aceves (Set-Up) – I know that he’s been “penciled in” for the rotation, but I can’t envision a scenario where the bullpen loses both Aceves and Bard.  With Cherington still searching high and low for legitimate starting pitching help both via the trade and free agent markets, it seems safe to say the front office feels more comfortable with one of them remaining in the pen.  Additionally, with Bailey and Melancon on the roster, moving Bard to relief sends an odd message.  That leaves Aceves as the one going back to the pen.  Truth be told, that’s probably where he belongs.  Much of Aceves’s value is tied to his versatility.  He can start, provide long relief, and fill high leverage innings late in the game. As such, it’s in the Red Sox’s best interest to keep him in a position where he can be the most effective and provide the most value.

Matt Albers (Middle Relief) – When Bobby Jenks went down with a back injury early on in the 2011 season, Albers unexpectedly stepped into the role as the seventh inning set-up man and flourished.  That is, until the calendar hit August 1st, and then everything went to pot.  In August (6.37 FIP) and September (7.33), his walk and home run rates skyrocketed, and his effectiveness cratered.  He blew several key leads down the stretch, and Terry Francona eventually removed him from high-leverage situations.  As a result of his late season struggles, Albers will take a lesser role in the bullpen this year.  If he can regain his early-2011 season form, he could become a very effective reliever.  Unfortunately, track record is not on his side.

Franklin Morales (Middle Relief) – Over the years, baseball people have gushed over Morales’s potential.  Some felt he could have been a top of the rotation starting pitcher, while others fancied him as a dominant closer.  Now 26 years old, he’s achieved neither of these expectations, and it seems very unlikely he ever will.  Still, he’s a hard throwing lefty with an above-average curve and a nasty change-up.  If he can ever learn to harness his stuff, he’s more than capable of putting together a few dominant seasons out of the bullpen.

Andrew Miller (LOOGY) – Miller’s adventures in the rotation last year were nothing short of a disaster (5.41 FIP).  If the Red Sox want to get anything out of the former first round pick, they’ll need to move him to the bullpen and convert him to a LOOGY.  Last season, Miller had a 2.01 FIP and 4.17 K/BB ratio against lefties versus a 6.37 FIP and 0.71 K/BB ratio against righties.  You could argue that last season’s sample is not large enough to make that conclusion (and you would be right), but his career platoon splits don’t help his case.

Michael Bowden (Mop-Up) – After a successful run as Pawtucket’s closer last season, it looks like Bowden will finally has a serious chance to stick with the big club.  He’ll likely serve in long relief during low leverage, mop-up type situations to start.  If he can prove to be effective in that role (something he’s yet to prove at the major league level), it’s possible he’ll be given higher leverage situations.  In order for that to happen, he’ll need to induce a lot more swings, and generate a few more strikeouts.