BOSTON -- LeBron James led the new-look Cavaliers to a blowout in Boston with an individual performance reminiscent of the rivalry's heyday.
And this time, Paul Pierce was sitting courtside in street clothes, unable to do anything about it.
With the former Celtics great waiting to see his No. 34 raised to the Boston Garden rafters, James shook off a first-quarter leg injury to score 24 points with 10 assists and eight rebounds to give Cleveland a 121-99 victory on Sunday.
In their first appearances since being acquired at the trade deadline, Jordan Clarkson scored 17 points, Rodney Hood had 15, George Hill had 12 and Larry Nance Jr. scored five. The foursome practiced with the Cavs for the first time on Saturday.
"I know the guys that are here are very excited about this opportunity," James said. "It's my job to as the leader of this team to make sure that I acclimate the new four guys to be around a culture that's built around winning."
James scored 13 in the second quarter -- eight of them during a 13-2 run that turned a one-point deficit into a double-digit lead. The Celtics made it 64-55 on the first basket of the third quarter but never got within 10 again.
As the Cavaliers opened a 27-point lead midway through the fourth, the crowd began chanting "We want Paul Pierce!" But he remained in his baseline seat, awaiting the postgame ceremony that would raise his No. 34 to the TD Garden rafters -- the 23rd person in the history of the NBA's most-decorated franchise to be so honored.
"It definitely gave me chills, especially with LeBron out there," Pierce told reporters afterward. "I wanted to be out there."
The current Celtics, who have spent much of the season in first place in the East, could have used him.
"Yeah, we stunk," coach Brad Stevens said. "But they were really good. They had a lot to do with that."
Terry Rozier scored 21 with nine assists and Kyrie Irving scored 18 against his former team before sitting out the fourth quarter. The Celtics have lost three of four to fall behind Toronto in the Eastern Conference playoff race.
The Cavaliers, who have won three straight, are 5 1/2 games behind Boston. To help make a push for their fourth straight NBA finals, Cleveland traded away six players and acquired four at the deadline.
"All of our new guys performed and played well," coach Tyronn Lue said. "So that's a good sign."
Pierce watched the game from a baseline seat, under the basket where the Celtics scored 42 points in the fourth quarter of Game 6 of the finals to clinch their 17th NBA championship. On the other side of the basket were former coach Doc Rivers and former teammates Kevin Garnett, Rajon Rondo and Antoine Walker.
Timeouts featured tribute videos from Rivers, Magic Johnson, Kobe Bryant and Pierce's college coach, Roy Williams.
After his family joined him in hoisting the retired number banner to the rafters, Pierce said having his number retired by the NBA's most-decorated franchise is the ultimate honor -- bigger than the Hall of Fame.
"When you're forever with the Celtics, you're forever," he said.
James banged into Aron Baynes in the lane with about five minutes left in the first quarter and hobbled off the court, favoring his right leg. He came back in with nine minutes left in the half and hit a jumper to tie it 40-all before his outburst that helped the Cavs pull away.
He sat out the fourth quarter, losing the chance for an 11th triple-double this season and third straight. James said he took a knee to the quad muscle but hoped to be fully recovered before playing the Thunder on Tuesday night.
"Baynes is a big boy. He should be on `Game of Thrones," James said. "Him and Steven Adams, and I've got to see him next."
The trades mooted a mini controversy over whether the Celtics would honor Isaiah Thomas in his return to Boston. A fan favorite during his two-plus seasons in green, Thomas was traded last summer in the deal that brought Irving to the Celtics.
Thomas balked at being recognized on his first visit back with the Cavaliers because he was injured. And Pierce balked at sharing the stage with him on Sunday, Cleveland's only other trip to Boston.
But Thomas was traded to the Los Angeles Lakers at the deadline, meaning he isn't scheduled to return to TD Garden this year.
Stevens said Marcus Smart continues to recover from a lacerated right hand, which has kept him out since he cut his hand on broken glass at the team hotel on Jan. 24 and needed stitches to close the wound.
"Not going to expect to see him on Wednesday night," Stevens said. "Hopeful that he will be back and ready to go after the All-Star break. But we'll see."
Cavaliers: At Oklahoma City on Tuesday.
Celtics: Host the Los Angeles Clippers on Wednesday night.
More NBA basketball: https://apnews.com/tag/NBAbasketball
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