Uehara was unavailable Saturday against the Washington Nationals, the third straight day he was unable to pitch. The first Japanese-born player in Orioles history began the season on the DL and has appeared in six games in relief since his return on May 6.
Uehara also missed time last season with elbow tendinitis, and said through a translator that this injury is "in a similar area."
He said he felt discomfort in his elbow during his last appearance, a 29-pitch effort Wednesday in Texas.
Orioles manager Dave Trembley said Uehara probably won't be available Sunday. When asked if the pitcher might be headed toward the DL, Trembley responded, "I think that's a consideration."
Uehara came to the Orioles last season with high hopes of extending the success he enjoyed in Japan, but his career in the major leagues has been marred by one injury after another. As a starter last season, a strained hamstring landed him on the DL from May 23 to June 11, and Uehara returned to the disabled list on June 24 with elbow tendinitis.
That ended his season, and the 35-year-old hasn't proven to be any less fragile in the bullpen.
"Everything is my fault," he said in the Baltimore clubhouse.
Asked when he might pitch again, Uehara said, "At this moment, I can't really say."
He did, however, say, "The bad part is over, so hopefully I'll recover soon."
With Uehara unavailable, and with several other relievers overworked, Trembley was forced to keep starter Brad Bergesen in the game longer than he would have preferred in Saturday's 7-6 defeat.
"You're in a situation there where you have to go with who you think is your best guy right there," Trembley said. "The back end of your bullpen is pretty well beat up. You've got some guys who have been extended. You've got a guy who's not available, so you do what you think is the best thing, and for me Bergesen was my best option."
Bergesen was pulled during a four-run sixth inning that enabled Washington to erase a 6-3 deficit.