WALTHAM – When you go through what Doc Rivers  went through on Sunday in Chicago, you’ll look for any good reason to smile.
While watching the fifth inning of Sunday night’s Red Sox-Yankees game on TV, he got that reason.
Red Sox  speedster Jacoby Ellsbury  took off for home on a straight steal with the bases loaded and just barely made it under the tag of Jorge Posada , sparking the Red Sox to their 10th straight win.
“That was cool,” said Rivers, who has cheered hard for the Red Sox since coming to town in 2004. “That actually put a smile on my face. One of the few smiles I had on my face was that play. Thank gosh that happened.”
And after coming back from Chicago and getting back to his Boston apartment following his team’s 121-118 double-overtime loss in Game 4, he was in the mood to put on something to just take him away.
And with the Red Sox winning their 10th straight, Rivers was also looking for a little Boston sports karma.
“I’m happy with the way they’re playing,” Rivers said. “I want some of that. I want us to do that, too.”
Following Sunday’s 3-hour, 33-minute marathon, the team did not practice today. Instead they watched film and held a very light shootaround. The Celtics  play the Bulls in Game 5 Tuesday night at the Garden, with the series tied, 2-2.
“We may not have even needed the film, to be honest,” Rivers said. “But sometimes when you lose the way you lost (Sunday) and execution is not perfect, I think it’s just better to get the guys together and put them in the same locker room. Hell, I should’ve just sat in there and sang songs or whatever. Kumbaya or whatever.