Bailey experienced discomfort while increasing his throwing workload as he prepared for Spring Training. Exams indicated that the ulnar collateral ligament and flexor mass tendon are healthy. Bailey had previously had surgery in both areas, but his offseason throwing program had been going well in Texas, making this latest setback somewhat surprising.
"The discomfort was very recent," Reds general manager Dick Williams said. "We got it looked at very quickly, and this was diagnosed. We acted as quickly as we could."
The Reds expect Bailey to resume throwing in 4-6 weeks. He is likely to begin the season on the disabled list.
Bailey, 30, returned July 31 after missing 15 months because of Tommy John surgery on his right elbow. In six starts, he was 2-3 with a 6.65 ERA before he was shut down again with right biceps tenderness.
Since going on the DL with his flexor mass tendon tear in August 2014, Bailey has been limited to eight starts. He is entering the fourth year of a six-year, $105 million contract, and he has $68 million remaining on the pact.
Without Bailey in the rotation, another spot opens up in what should be a deep competition. Among starters expected to compete for spots are prospects Robert Stephenson, Cody Reed and Amir Garrett, along with Tim Adleman and non-roster invitee Bronson Arroyo, who is also trying to come back from two years out due to arm injuries.
Williams wasn't planning on adding another pitcher to the mix. It's possible that Bailey won't miss too much of the season, but the GM wasn't ready to determine when he could return to pitching in games.
"We won't do a knee-jerk signing as a result of this," Williams said. "I'd hate to speculate this soon. We haven't even drawn out his rehab schedule yet. It's a little early to know."
Mark Sheldon has covered the Reds for MLB.com since 2006, and previously covered the Twins from 2001-05. Follow him on Twitter @m_sheldon and Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.