Red Sox have limited options in bullpen

NEW YORK -- With the bullpen sputtering badly in front of Junichi Tazawa and Koji Uehara of late, the Red Sox would love to be able to work in a new arm or two. However, the lack of rotation depth thanks to the injuries to Clay Buchholz, Rick Porcello and Brian Johnson has limited what the club can do.

For instance, Joe Kelly, who has struggled all season as a starter, could rejuvenate in a setup role. But that's not on the table right now as manager John Farrell needs Kelly to keep taking the ball every fifth day.

Righty reliever Ryan Cook, recently acquired from the Oakland Athletics for cash, can't be used at the Major League level for nine more days after being optioned to Triple-A Pawtucket to make room for Henry Owens on Tuesday.

"It's a discussion that [general manager] Ben [Cherington] and I have that's ongoing," said Farrell. "To say that there's someone walking through the door today, that's not the case, but we've got to do better than what's been taking place in our bullpen."

Matt Barnes, who has worked mainly out of the bullpen in his stints with the Red Sox this season, is getting stretched back out as a starter at Triple-A.

"It's twofold," said Farrell. "One, we've got to start to create some starter depth in light of Johnson's injury. Second, we've taken a number of trips to the big leagues with Barnes in a bullpen role. I can't tell you at this point that we would not see him here in a starter's role, but we've got to get him stretched out first."