Now, just days before the season starts, Bailey has been told he needs surgery on his right thumb, according to major league sources.

Bailey was examined by team doctors in Boston on Monday and on Tuesday will see Dr. Thomas Graham, a hand specialist at the Cleveland Clinic. If Graham agrees with the recommendation for surgery, it could happen later that day.

Graham performed surgery on Kevin Youkilis and Jarrod Saltalamacchia in 2010. Youkilis had a torn muscle in his right thumb and Saltalamacchia a torn ligament in his left thumb.

The Red Sox open the season on Thursday in Detroit. It is uncertain how long Bailey would be out.

“When a player is injured I always am very concerned and always try to make alternative plans. If he jumps right back in, then I’m pleasantly surprised,’’ manager Bobby Valentine said. “When guys are hurt, they’re hurt and he couldn’t pitch for a couple of days, you know?’’

It is uncertain how Bailey was injured. All that is known is that he threw 26 pitches in a minor league game last Wednesday and has not pitched since.

Because of the long layoff, it is almost certain Bailey will start the season on the disabled list for the second consecutive season, whether surgery is required or not.

Bailey strained his forearm in spring training last season and did not return until May 29.

In 2010, he had minor elbow surgery in September and knee surgery after the season in 2009.

Bailey strained a muscle behind his shoulder on the second day of camp with the Sox during physical testing. That kept him out until March 12. But he was on track to make Opening Day before the thumb injury.

The Red Sox traded outfielder Josh Reddick and two prospects to Oakland on Dec. 28 for Bailey and outfielder Ryan Sweeney.

“We had a chance to look into Bailey’s medical history and get to know a lot more about what he’s gone through,’’ Sox general manager Ben Cherington said at the time. “We’re very confident that he will come into camp ready to go.’’

Without Bailey, an already thin Red Sox bullpen will turn to Mark Melancon and Alfredo Aceves as replacements. Melancon has 20 career saves, all with the Houston Astros last season. Aceves has four career saves.

“I’m ready for whatever they throw at me,’’ Melancon said. “If they need me to close, I’ve done that before. It’s the kind of situation that I like.’’

Aceves was told by Valentine to be prepared to pitch in the eighth or ninth inning. If Bailey is out for an extended period, the Sox could designate Melancon or Aceves as the closer. There are no plans at the moment to return newly crowned No. 5 starter Daniel Bard to the bullpen.

Meanwhile, No. 2 starter Josh Beckett also has a right thumb injury. But Valentine said he “totally’’ expects Beckett to start against the Tigers as planned on Friday.

Beckett was in San Antonio on Monday to be examined by Dr. Mark Bagg, a hand specialist.

“If he needed to talk to me, he was going to talk to me. He didn’t talk to me, so I think he was fine,’’ Valentine said.

Beckett threw a lengthy bullpen session on Sunday and did not miss any of his starts this spring. He allowed two earned runs on seven hits over 19 innings against major league competition.

“He threw 100 pitches yesterday and felt great, hit location,’’ Valentine said. “He’s had a little situation that he’s getting taken care of today just for peace of mind.

“He said he felt really good. I talked to the trainers and Bob [McClure, the pitching coach]. What was really good about the last couple of times that he’s thrown is he’s had good command.’’

Valentine said Beckett has had “a little history’’ with his thumb. Beckett is expected to join the team in Detroit on Wednesday.

That two prominent pitchers experienced thumb injuries at the same time is unusual.

“Interesting, isn’t it?’’ Valentine said. “No thumb wrestling is allowed. We took that out of the program.’’

Peter Abraham can be reached at pabraham@globe.com. Follow him on Twitter @PeteAbe.