Celtics coach Doc Rivers said the surgery will be performed by team doctor Brian McKeon. The Celtics play host to the Philadelphia 76ers in Game 7 of the Eastern Conference semifinals on Saturday (ABC, 8 p.m. ET).
"It's disappointing," Rivers said of losing Bradley. "Obviously when a player goes down, that's disappointing, especially on what Avery has given us this year. His growth this year has been terrific, and it's been great, and he's become a very valuable piece to our basketball team."
A league source told ESPNBoston.com on Thursday that Bradley is looking at a four-month rehab, and that the team hopes he will be able to participate in training camp.
Rivers acknowledged the weight of losing Bradley, particularly on the defensive end and, according to ESPN Stats & Information, his absence will take away the Celtics' best five-man lineup this postseason: When Bradley, Rajon Rondo, Paul Pierce, Brandon Bass and Kevin Garnett have been on the court together, the Celtics have outscored opponents by 53 points. Their next-best lineup has outscored opponents by only 18 points (Ray Allen, Garnett, Pierce, Rondo and Mickael Pietrus).
A source described Bradley as despondent over not being able to return to the court.
"Avery's a big blow, yeah, there's no doubt," Rivers said. "If I'm the other guys on any other team, and the fact that I don't have to play against Avery Bradley, I would sleep a little better. No one wants to play against Avery. Our guys don't want to play against him in practice. He's a pain in the [butt] defensively. That's what he does."
Bradley has endured a number of shoulder dislocations this season, including three in the postseason. After the shoulder came out in a Game 4 loss to the 76ers, doctors determined it was too risky to put him back on the court with the potential for a more serious injury, according to a source. Bradley has missed Games 5 and 6.
A first-round pick (19th overall) in the 2010 draft, Bradley will miss his third consecutive summer league, as well. After being drafted, he underwent ankle surgery related to a draft workout that likely caused him to slide late in the first round. He missed both summer league and most of training camp that year. Last offseason, the lockout wiped out summer ball and shortened training camp.
Despite all of that missed activity, Bradley emerged as a key member of the Celtics' rotation, taking over the starting shooting guard role when Allen battled an ankle injury late in the regular season.
Bradley's tireless on-the-ball defense has drawn notice across the league, and he earned a couple of coaches' votes for the NBA's All-Defensive teams (including one first-team vote).
Greg Payne is a contributor to ESPNBoston.com. Information from ESPNBoston.com's Chris Forsberg was used in this report.