In 2003, Donnelly made the American League All-Star team as a setup man, eventually posting a 1.58 season ERA in 74 innings. He remained a fixture in the Angels' 'pen until he was traded to the Red Sox for Minor Leaguer Phil Seibel in December 2006.
As time passed, Donnelly developed pain in his forearm.
"It's been going on for several years," he said. "It's been going on. But there's really been no signs of it breaking down over the last three years, until now."
On June 15 against the Giants, Donnelly felt tightness in his forearm while warming up, and the Red Sox shut him down. An MRI showed swelling in the muscle.
Twice Donnelly attempted to return from the injury, only to experience setbacks.
"We tried everything ... to come back," Donnelly said. "By doing the surgery now, it gives me an opportunity to pitch next year and, you know, four, five years down the line. As opposed to just keeping fighting through, day by day, wondering when the day's going to come that it's just [not going to work]."
"He gave a pretty valiant effort," said manager Terry Francona. "Sometimes you come to the realization, 'OK, it's time to get fixed.'"
In many ways, the news for the supremely competitive Donnelly came as a relief. He spent 10 years in the Minors with eight organizations before he made the Majors. He persisted through the pain. Now, he has no choice but to sit. No more "running in sand" or "spinning your wheels," performing without knowing the mysterious source of the elbow pain.
Red Sox general manager Theo Epstein said Donnelly knew he needed surgery as long ago as the end of the team's recent road trip. But he withheld the news, allowing Epstein to work from a bargaining position of strength while the team pursued a right-hander before the trade deadline.
"We certainly appreciate that and wish him the best with his recovery," Epstein said.
The recommended recovery period from Tommy John surgery usually runs between a year and two years. But Donnelly told the media he "should be back within a year or less."
"Knowing his personality, day in and day out, he's probably going to move ... up [the recovery period] a little bit," said fellow reliever Mike Timlin. "He may set the record."
Said Donnelly, "This is what we're going to do: we're going to go fix it and make it right and continue on pitching after that."
Achy shoulder improves: Timlin was unavailable again on Tuesday night after missing the previous week with an "achy" shoulder. But he noted significant progress after throwing a side session earlier in the day.
"Felt great," Timlin said. "Back to normal."
"Well, whatever relatively ... is normal," he added.
"We're pleased," said Francona. "Does it make him available tomorrow night? Yeah, he'll be available. The next night would be perfect. But, again, we'll mix and match and he'll be available tomorrow."
On deck: Francona has not yet announced a starter for Wednesday night's 7:05 p.m. ET game against Baltimore. With lefty Kason Gabbard joining Texas as the key chip in the Eric Gagne trade, his slot is as yet unoccupied. Former fifth starter Julian Tavarez could step in.