Just as the Celtics  began to solve one problem, they ran into another in the fourth quarter against the Pacers. The Celtics played one of their best offensive games in weeks, but ran out of steam at the end of a back-to-back in a 107-100 loss. They made sloppy passes and missed free throws — two sure signs of fatigue — and were outscored 26-15 in the fourth quarter. In other words, they were playing the second game of a back-to-back on the road.
Here’s how it happened:
WHAT WENT WRONG
Foul trouble for the bigs: Kevin Garnett  picked up his second foul with five minutes to go in the first quarter and the Celtics leading 22-12. By the time he returned the Pacers had a 37-35 lead. Garnett didn’t stick around long, getting his third foul two minutes later on an over-the back call. Nenad Krstic  also spent the first half in foul trouble, which allowed the next thing to happen …
Roy Hibbert  went off: Glen Davis  does a lot of things for the Celtics and one of the most important is his willingness to guard taller players. Davis typically use his bulk to keep bigger post players out of the paint and his nimble feet to get to a spot on the floor and draw charges. Both skills were useless against Hibbert who simply shot over him and made 9-of-10 in the first half. Davis played well for the most part, but having to guard Hibbert wouldn’t have been in his job description if Garnett and Krstic hadn’t spent the night in foul trouble.
Jeff Green  needed to assert himself: Over the last few weeks, Jeff Green has become the kind of offensive energizer the Celtics were looking for when they acquired him from Oklahoma City. Aside from getting to the line at the start of the fourth quarter, Green offered little in the way of an offensive spark in his 28 minutes of action.
WHAT WENT RIGHT
Rondo was Rondo: Rajon Rondo  wasn’t supposed to play Monday night. An hour before the game tipped off, Doc Rivers  told reporters in Indiana that his point guard would sit out a second straight game to rest his injured pinky finger. That changed about 45 minutes later when Rondo took the floor for warmups. In the first quarter he made all five of his shots (all on layups) and made two free throws. This is the Rondo they have been waiting for.
Third quarter rally: This would have been very easy for the Celtics to pack it in at halftime. They were down eight, it was the second game of a back-to-back and they weren’t getting the calls from the officials. Instead, they put together an impressive third quarter run that put 36 points on the board and gave them back the lead.
Paul Pierce  picks up his game: Lost in all the angst over Rondo is that Paul Pierce has been the other missing ingredient in the Celtics’ offense. He’s shooting just 26 percent from 3-point range since February and while his percentages have dropped, his turnovers have risen. But Pierce shot the ball better — making 8-of-13 and going 3-for-4 from behind the arc.