While it has been mostly agreed upon that the Red Sox's biggest weakness heading into 2013 will be their rotation, they have made just one move -- signing Ryan Dempster -- to strengthen that unit. In the meantime, they've built themselves a very formidable bullpen, bringing in both Joel Hanrahan and Koji Uehara to pitch in the later innings. For a team coming off a 69-win season, it would be assumed that the bullpen would be the least important part of the team to improve. However, having a good bullpen can steal a team a lot of wins in extremely close games -- just ask the 2012 Orioles.
After last season's surprise run to the playoffs, luck was said to have played a major role for Baltimore's success. They had a 29-9 record in one-run games in 2012, as well as a 16-2 record in extra inning games -- both of which were the best records in all of baseball in such games. While that performance probably isn't sustainable, it doesn't mean it was all luck. In games that are separated by just a run, or that go to extra innings, bullpens are used pretty much every time. Last year, the Orioles had one of the best bullpens in the league, posting a 3.00 ERA -- fifth-best in baseball -- over 545-1/3 innings, the fourth-most in the game.
The Red Sox may be longshot contenders in 2013, but a good bullpen can do enough to push a team over the top. As their roster stands right now, Boston has Hanrahan, Uehara, Andrew Bailey, Junichi Tazawa, Andrew Miller, Franklin Morales, Craig Breslow and Alfredo Aceves in their bullpen. Those first four guys can all claim to be formidable options for the "closer" role, while Miller and Morales have had success as left-handed relievers.
So, where does the team's bullpen rank amongst other bullpens in baseball? First, we'll look at them compared to the rest of the AL East. Baltimore's bullpen had a lot of success last year, and figures to be very good again in 2013. Their closer, Jim Johnson, had his third straight season with a sub-3.30 FIP, as well as a sub-3.50 ERA. Set-up man Pedro Strop pitched well as well, though, his consistently high walk rates will likely come back to hurt him at some point. Baltimore's bullpen should still be very good, but they don't look to have the depth in the late-innings that the Sox currently possess. The Yankees will be getting Mariano Rivera back in the bullpen, but it looks like they'll also be losing free agent Rafael Soriano. They will be strong in the eighth and ninth innings, with Rivera and David Robertson, but they have some question marks after that. Tampa Bay's bullpen always manages to be surprisingly good, but another high-quality season from Fernando Rodney seems unlikely. Finally, for all of the great moves Toronto has made this winter, they haven't done too much to strengthen their relief corps. In the end, I think it's safe to say that, on January 2, the Red Sox have the division's best bullpen.
Looking now at the rest of baseball, the Red Sox still stack up pretty well. The two best pens in the game last year, by ERA, were Atlanta's and Cincinnati's. This makes sense, as they had the two best closers in all of MLB, by a pretty fair margin. Beyond the great Craig Kimbrel, the Braves also have Jonny Venters and Jordan Walden for the late innings, both very formidable set-up men. In Cincinnati, much of their success was built upon a phenomenal season from Aroldis Chapman. They've since brought in Jonathan Broxton to take care of their closing duties, as Chapman will take his heat to the rotation. Broxton and Sean Marshall still make up a good back of the bullpen, but it's not as appealing as having Chapman back there.
Looking around the league, I think it's safe to say the Red Sox bullpen could very well be one of the best five units in baseball. Of course, relief pitching is tough to predict, and the offseason is still going, which means another bullpen-altering move could happen. Right now, though, they are very good in the late innings. Between Hanrahan and Bailey, they have two "proven closers," while Uehara has had a lot of success pitching in the seventh and eighth innings in the past. Tazawa also showed flashes of greatness last year, and should see a lot of time at the end of games. The starting rotation still has plenty of question marks, and the lineup still looks a bit incomplete, especially with the ongoing Napoli negotiations. Their bullpen looks very strong, though, especially in the late innings. If the starters can keep games close to the sixth inning, the relievers should be able to win them a lot of games. It's not the most efficient strategy for winning, but a good bullpen can certainly carry a team to the playoffs. Just ask the 2012 Orioles.