Celtics coach Doc Rivers, who has been linked to retirement in rumors himself, was asked about Phil Jackson's departure prior to Game 4 between Miami and Boston on Monday night.

The Mavericks completed a four-game sweep of the Lakers on Sunday, a result that sent shockwaves through the NBA.

"It's too bad, because he's the greatest coach, having won all the championships, maybe in American sports, not just basketball," Rivers said of Jackson's retirement. "Having been around the league, you don't like seeing guys leave the game that contribute to the game. I wouldn't be shocked someday to see him back, personally, but I understand what he's doing."

Rivers also commented on the demise of the Lakers, which came much sooner than people expected.

"I don't know if 'stunned' would be the right word for it, but you know it happens," he said. "Once you're down 3-0, you give everybody enough time to realize that it could happen. I think everyone was surprised.

"I don't know what to say, but it was quicker than we all saw it coming."