NEW ORLEANS -- The Boston Celtics were coming off a listless loss at Houston and were playing just as poorly against New Orleans. Then they went back to what got them to the top of the Eastern Conference -- stifling defense and terrific shooting.
Allen also had a key offensive rebound that led to Glen Davis' two foul shots that made it 87-83 with 15.2 seconds remaining. Davis, a Baton Rouge, La., native who played at nearby LSU, also had 20 points.
The Celtics trailed 56-41 early in the third quarter but closed the period with a 23-6 run to go ahead 67-64 and never trailed again.
Boston, the NBA leader in field-goal percentage, shot 12 of 16 (75 percent) in the third quarter. The Celtics, who also lead the NBA in scoring defense, held the Hornets to 34 points in the second half and 6-of-21 shooting (28.6 percent) in the third quarter.
"The energy level changed," Davis said. "We started doing the things we know how to do best. We changed the tempo of the game and we made them uncomfortable in the things they had been doing."
The Celtics snapped a three-game road losing streak and moved back into a tie with idle Chicago for the best record in the conference.
"We played so poorly last night and we really just started the game the same way today," coach Doc Rivers said. "It meant a lot to the guys to come back. They wanted this win."
"It's going to be hard for us to win if I play like that," said Paul, who did have 15 assists. "I've got to do better. We lose by four points, and I play like that."
Paul barely grazed the rim on a runner in the lane that would have tied it at 83 late in the game, and Emeka Okafor was tied up for a jump ball as he went for the putback. The Hornets controlled the tip, but Belinelli was stripped as he drove to the basket.
Kevin Garnett scored to give the Celtics an 85-81 lead with 57.4 seconds remaining. West followed with a driving bank shot, but the Hornets couldn't get any closer.
Allen grabbed a rebound off a miss from Davis seconds later. After Paul Pierce called a timeout to avoid a turnover while being trapped near midcourt, Davis was fouled and hit both free throws.
Okafor scored on a putback, but the Hornets could not prevent Allen, one of the best foul shooters in NBA history, from getting the inbounds pass.
Garnett had 12 points and nine rebounds. Pierce went 1 for 9 from the floor, finishing with nine points and six assists.
The Celtics' huge spurt in the third quarter started when Allen took an inbounds pass with 2 seconds left on the shot clock and drained a 3-pointer. Davis then scored twice in succession and Allen had three baskets, the last on a give-and-go from Garnett that put the Celtics ahead 65-64.
"The 3 Ray Allen hit out of the timeout was inexcusable," New Orleans coach Monty Williams said. "That should never happen. What it boiled down to is we didn't have the toughness they had."
Davis finished the third quarter with another easy layup, and Delonte West converted a three-point play at the start of the fourth to give the Celtics a 70-64 lead.
The Hornets managed just eight points in the final 10:45 of the third and two -- on a West bucket -- in the last six minutes.
Okafor had 10 points and 11 rebounds for the Hornets. Trevor Ariza also had 10 points.
The Hornets do not play again until Thursday at Utah. The layoff is their longest of the season other than the All-Star break. ... Boston is 2-3 in the second game when it plays on the road for two consecutive days.
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