Farrell said Edward Mujica will be the primary closer in the meantime, and Junichi Tazawa, Alexi Ogando and Tommy Laynecould pitch the ninth as well, depending on matchups.
Uehara's bullpen session was his first since he initially sustained the injury. The Red Sox had hoped he would be able to pitch in a few spring training games this week.
Uehara, who turns 40 on Friday, signed a two-year contract with the Red Sox in October. He has been Boston's closer for the past two seasons, compiling 47 saves.
- Dan Gartland