NEW YORK (AP) -- The Boston-New York rivalry returned Monday, and the Celtics nearly got too caught up in it.
The Celtics made an easy victory hard on themselves by losing their composure, but Kevin Garnett had 20 points, 13 rebounds and seven assists to help them recover and beat the Knicks 109-93 Monday.
Celtics players lost their focus in the third quarter,when leading scorer Paul Pierce was ejected along with New York's Quentin Richardson after both picked up two technical fouls for jawing with each other during the period. Kendrick Perkins also picked up a technical during the quarter.
"It wasn't just Paul. It was five of us. All of us running our mouths instead of playing basketball," Celtics coach Doc Rivers said. "You don't need to run your mouth. I wasn't happy with that.
"We deserved the techs. We deserved the ejections. We deserved everything we got and we're very lucky to win the game. We're playing a team that's playing terrific, you get caught up in that [junk] and you lose the game."
Neither Pierce nor Richardson spoke to the media after the game.
"They traded off Quentin Richardson for Paul Pierce and I think they'll take that any day. So we just got to keep our composure in situations like that," Celtics guard Eddie House said. "We know when we get up on teams, teams are going to try to pull everything out of their hats, so we just have to be prepared for that and aware of that and handle it a little better than we did tonight."
Perkins scored 22 of his career-high 24 points in the first half for Boston (33-6), which has won three straight following the only rough patch in its season, a stretch of three losses in four games. Ray Allen added 17 points and Rajon Rondo had 14 in his return to the lineup after missing two games with a sore lower back.
"Guys are playing with a lot of passion, lot of emotion, this is a big game for them," Garnett said. "They've been playing together. You have to expect the emotions to be high."
With the victory, Rivers clinched the right to coach the Eastern Conference in next month's All-Star Game.
Zach Randolph had 24 points and 15 rebounds for the Knicks, who had won four of five during the best stretch of a miserable season. New York reached the halfway point of the schedule at 13-28.
"Their savvy throughout the course of the game, they were able to pick us apart," Knicks coach Isiah Thomas said.
It was the first meeting since the Celtics crushed the Knicks 104-59 on national television Nov. 29 in Boston, New York's third-worst loss and its second-worst scoring performance of the shot-clock era. It was also the biggest victory in the history of the Celtics-Knicks rivalry.
Speaking of New York and Boston rivalries, Plaxico Burress, R.W. McQuarters, Aaron Ross and Steve Smith sat courtside, a day after helping the Giants win the NFC championship and a spot in the Super Bowl with Sunday's 23-20 overtime victory in Green Bay.
They got huge ovations when shown on the overhead scoreboard during a third-quarter timeout, and the noise in the building perhaps helped the Knicks get back into the game. New York trimmed what had been a 19-point deficit to seven early in the fourth quarter, but Boston quickly pulled away again behind Garnett, who scored eight points in the period.
At least the Knicks made the effort this time. Not everyone thought they did during the blowout in Boston, with players having to defend themselves against accusations they quit.
This one seemed headed the same way after a flurry by Pierce gave Boston an 18-point lead midway through the third quarter. But he got involved in the back-and-forth with Richardson later in the period, and it seemed to distract the Celtics.
Perkins made his first six shots and scored 15 points in the first quarter. The Celtics led by 11 before settling for a 29-23 advantage after one period.
The Knicks were within three late in the first half, but the Celtics scored the final 11 points. They took advantage of four New York turnovers to get their break going, and had a 59-45 lead after Rondo's jumper at the buzzer.
Thomas shook up his lineup to start the second half, benching Curry, Richardson and Fred Jones. Robinson, David Lee and Jared Jeffries started instead, helping the Knicks pull within nine. Pierce then scored seven points in a 9-0 spurt that made it 70-52 midway through the third quarter.
The Knicks fell to 16-6 on Martin Luther King Jr. day. All but one of those games were at home. ... Boston improved to 10-0 against Atlantic Division opponents.
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