Boston Celtics coach Doc Rivers may not finish out his contract with the team.  Rivers is reportedly considering retiring this summer.  A source said on Wednesday the 51-year-old coach feels it "may be time for a change," ESPN reports.

Although Celtics team president Danny Ainge has said that Rivers will return to the sideline next season, growing speculation suggests Rivers will retire this summer.

"Doc loves coaching," a source told ESPN.  "He loves coaching in Boston.  But he feels it may be time for a change."

Rivers, who has attended the Celtics pre-draft workouts, has three years left on his $21 million contract with Boston.

Talk about Rivers retiring has floated around the league for last few seasons.  He's spoken in the past about wanting to spend more time with his family.  His son, Austin, just finished his rookie year with the New Orleans Pelicans (then Hornets).   With Austin's NBA career just beginning, Rivers could want to follow his son as a fan.

The Boston Globe reported on Sunday that Rivers is "seriously considering stepping down" from coaching.

"Rivers said he needed to 'detox' after the season and apologized for being inaccessible to reporters,"  Gary Washburn of the Globe wrote. "But he would not give any indication whether he will be back for a 10th season although president of basketball operations Danny Ainge told the Globe last month that Rivers had planned to return."

Asked if he was still involved in the Celtics' decision-making process, Rivers replied: "I'd rather not say."

Rivers' decision could depend on the futures of Kevin Garnett and Paul Pierce, the Celtics' core.  Garnett, 37, could choose to retire this summer.  Pierce, 35, might have his contract bought out by Celtics management.  It's unclear whether Rivers would want to stick around for what'd essentially be a new Boston Celtics team.

If his decision to return is tied to Pierce, the decision should come soon.  Boston must decide Pierce's future with the team by June 30.  Rivers concluded his conversation with Washburn by saying he planned to speak "soon" to media about his plans.