NBA via Boston Celtics(NEW YORK) -- The Boston Celtics have made their roster stronger this offseason, but Guard Avery Bradley will still undergo shoulder surgery and could miss the start of next season as a result.

Bradley needed shoulder surgery during the Eastern Conference Finals, but will need yet another surgery to get ready for next season. The team had waited for his left shoulder to recover before having Bradley undergo another surgery, but this time on his right shoulder.

"It could be early in the season, it could be mid-December. We're just not sure," Celtics head coach Doc Rivers told the Boston Herald.

Even though Bradley averaged just 7.6 points per game this past season, he became a key member of the Celtics rotation and even pushed Ray Allen out of the starting lineup.

To help make up for the loss of Bradley, the Celtics have signed guard Jason Terry and are interested in guard Courtney Lee.

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