Who can pick up Edward Mujica’s slack?

Mandatory Credit: Adam Hunger-USA TODAY Sports

The bullpen was expected to be one of the greatest strengths on the Boston Red Sox entering the season. So far, that has held true as the Red Sox’ bullpen ERA of 3.15 ranks eighth in Major League Baseball. However, the Red Sox have posted that still respectable ERA despite major struggles from a key reliever in free agent signing Edward Mujica, who has posted a 9.00 ERA in 10 innings pitched. Hopefully Mujica will be able to turn around his early-season struggles, but if he cannot, then the Red Sox will be in need of a shutdown late inning reliever to pick up his slack. Who can step up?

So far, Mujica and Junichi Tazawa have been the main proprietors of the setup man role, but Mujica could move to a lesser role if he continues to struggle. Tazawa has been excellent this season with a 2.25 ERA and 10:1 K:BB ratio in 12 innings pitched, but he won’t be able to pitch every tight situation for the Red Sox. Luckily, another of Boston’s greatest virtues is the plethora of pitching depth both in the minor leagues and on the 25-man roster.

• Craig Breslow served in that role last season, as he was one of the more underrated assets on the World Championship team. He posted a 1.81 ERA in 59.2 innings last season and was nearly untouchable in the second half, posting a 0.65 ERA after the All-Star break. However, Breslow opened the 2014 season on the disabled list and has struggled a bit in his return with a 6.43 ERA in his first 7 innings (he is actually the only reliever other than Mujica with an ERA over 4.00).
• Andrew Miller was excellent before a season-ending foot injury last year, posting a 2.64 ERA and absurd 14.1 K/9 rate in 30.2 innings, and while he has cut down on the strikeouts a bit, he has been equally good to start 2014. He leads the Red Sox in appearances, with 14, and has a 2.31 ERA and career-best 3.50 K/BB in his first 11.2 innings pitched.
• Chris Capuano is something of a dark horse in this setup man race. A converted starter signed late this offseason, Capuano has been excellent in his first extended stint in the bullpen as he has posted a 1.20 ERA in his first 15 innings, and to give a further indication of his success, all two earned runs he allowed came in one game (he did not even allow a run until today’s 6-3 win).

Mujica and/or Breslow will have to ramp up their performance to fill the setup man role, because in this bullpen, it could easily be taken from them. Miller and Capuano have been excellent so far this season and if they can continue this performance, they certainly deserve a shot in high-leverage situations. Perhaps if all breaks right for the Red Sox, they could have four great late-inning relievers, two right-handed and two left-handed. They’ll just need Mujica and Breslow, both historically-consistent relievers, to turn around their slow starts and Miller and Capuano to continue their fast starts. For now, however, we’ll just wait and see how the roles materialize for this upcoming season.