There is no going back — at least not until next October, when a surgically repaired Rajon Rondo is presumably ready for more basketball. Another query about how the Celtics would have succeeded in their current style if the point guard was cooperative and healthy will set fire to Doc Rivers’ close-cropped head of hair. “The one thing I don’t want to get into is Rondo isn’t playing right now,” said the Celtics coach. “We keep going back to that, but he’s not playing right now. The guys I have playing are Jeff Green, Courtney Lee, Jason Terry. I prefer to focus on them.” A question earlier, a calmer Rivers expressed confidence that at some future time Rondo would function well within a scheme that values ball and player movement over his own dribbling and dominance of the ball. “Oh yeah. It should work,” said Rivers. “He would have the ball less at times. He would do more cutting and spacing.” The irony is that the final run of the season with Rondo was a six-game losing streak.