BOSTON – Charlotte Coach Paul Silas didn’t think his team had a chance when it trailed by 13 points in the fourth quarter. He didn’t count on Boston’s poor offense, defense and teamwork.

His young Bobcats had good reason to celebrate their 83-81 victory Friday night that left them two games out of the final playoff spot in the Eastern Conference.

The mood in the postgame locker room was joyous.

“It was unbelievable,” Silas said. “It’s just kind of indescribable.”

Celtics Coach Doc Rivers felt much differently. After all, one of the NBA’s best teams that should be building toward the playoffs lost for the sixth time in 10 games, and endured a 16-0 run in which the Bobcats took their first lead, 76-75, with 3:56 left.

“The way we’re playing shocks me. Our attitude shocks me,” he said. “I just think we’ve become very, very selfish, not just as far as trying to get our own (shots), but everything is about how we’re playing individually instead of how the team is playing.

“A guy struggles, he pouts, he moans. Everything is me, me, me on our team right now, feeling sorry for themselves instead of giving themselves to the team and playing.”

The Celtics led 66-53 entering the fourth quarter but were outscored 30-15 the rest of the way.

The Bobcats went on a 21-4 run that put them ahead 80-75 with 2:49 left on Gerald Henderson’s 18-footer. But Boston got the next six points to go up 81-80.

Then Dante Cunningham hit a go-ahead 15-foot jumper with 34 seconds left, Henderson sank a free throw and Boston’s last hopes ended when Ray Allen missed a 3-point attempt and Kevin Garnett failed on a jumper in the final five seconds.

“When you play a good team like this on the road, chances are you’re not going to blow them out,” said Henderson, who scored 15 points. “They’re just too good. You want to play the best that you can and just get yourself in a position to win at the end.”

Charlotte, led by D.J. White’s career-high 17 points, moved two games behind Indiana, which lost to Sacramento, for the eighth playoff spot in the East. Boston dropped two games behind the Chicago Bulls, who beat Memphis, for the best record in the East.

Boston was led by Paul Pierce with 18 points and Allen with 14.

“Our defense really broke down in the fourth quarter,” Pierce said. “Regardless of however our offense is going — it’s been struggling as of late — we still should be able to put together a defensive run.”

The Bobcats won without their leading scorer, Stephen Jackson, who had a strained hamstring, and their second-leading rebounder, Tyrus Thomas, who had bruised ribs.

“When you have too many breakdowns in the fourth quarter against an injury-riddled team, it’s frustrating,” Pierce said.

Charlotte made just one of its first 12 shots but trailed only 42-37 at halftime.

The Celtics dominated the third quarter, outscoring the Bobcats 24-16 and stayed on top 71-59 nearly three minutes into the fourth.

That’s when Charlotte began turning it around.

“I just didn’t know that we had it in us to really score like we did, especially in the fourth quarter,” Silas said. “Truthfully, I did not think we had a chance to win this ball game.”