Junichi Tazawa lands on DL with right shoulder impingement

As the Boston Red Sox made a trade to help their rotation, their bullpen took another hit.

Junichi Tazawa, one of the American League's most reliable setup men over the past few years, went on the 15-day disabled list Thursday with a right shoulder impingement. The move, retroactive to July 4, comes three days after closer Craig Kimbrel underwent surgery on his left knee that is expected to sideline him for three to six weeks.

Tazawa has a 3.62 ERA in 35 appearances. He hasn't pitched since July 3, complaining last week of shoulder fatigue, an issue that caused him to be shut down for the final month of last season. Since 2013, Tazawa has worked 222 1/3 innings, 12th most among American League relievers.

With Kimbrel and Tazawa sidelined, Koji Uehara and newly acquired Brad Ziegler are the most trustworthy late-inning options for Red Sox manager John Farrell, although right-handers Matt Barnes (2.93 ERA, 43 strikeouts in 43 innings) and Heath Hembree (2.00 ERA, 35 strikeouts in 36 innings) have had breakout seasons and are worthy of higher-leverage roles.

The Red Sox have made four trades within the past week, including a move Thursday night to acquire All-Star lefty Drew Pomeranz from the San Diego Padres for 18-year-old top pitching prospect Anderson Espinoza. After president of baseball operations Dave Dombrowski acquired Ziegler last Saturday, Dombrowski said the bullpen was "pretty well set."

Tazawa's injury might change things, although he's eligible to come off the disabled list as soon as July 19.

To fill Tazawa's spot on the roster, the Red Sox recalled right-hander William Cuevas from Triple-A Pawtucket.