"I know we're close, and at the end of the season they'll tell us," Celtics coach Doc Rivers said. "Both teams are really good, and really good teams don't lose at home. That's why it's really important for us to get this."
The Cavaliers (48-13) lead Boston (49-14) in winning percentage .787 to .778, though the Celtics took the lead in the head-to-head tiebreaker, 2-1, with an April 12 game in Cleveland remaining. Since the Celtics assembled their core of Pierce, Ray Allen and Kevin Garnett, neither team has won on the other's court, including the Eastern Conference semifinal last year that Boston won in seven games.
"They are a good team, with and without K.G.," Cavs coach Mike Brown said. "But I still feel like we can win on anybody's court."
Mo Williams scored 26 for Cleveland and LeBron James had 21, shooting just 5-of-15 from the field to go with 9-for-12 from the line. He spent the last 87 seconds of the game on the bench after the Cavaliers fell behind by 15 and couldn't make a run.
"Both teams know it takes on a different meaning because we may face each other late in the season," said James, who went 13:11 without a point in the second half as the Celtics turned a 55-52 lead into an 88-77 advantage. "At one point, somebody's going to have to get a win on the other's home court."
Garnett missed his seventh straight game for Boston with a strained knee muscle, and backup Glen "Big Baby" Davis was ejected in the third quarter for a flagrant foul. Powe filled in and reached season highs in both points and rebounds, giving the Celtics a spark with a blocked shot and a basket at the other end that opened a 94-83 lead.
After James missed a 3-pointer, Powe grabbed the rebound and Pierce hit a pair of free throws, then Powe dunked with 3:48 left to give the Celtics a 98-83 lead -- their biggest of the game.
"I know there's a lot depending on me coming in and playing well," said Powe, who had more points and rebounds than then entire Cavaliers bench. "It's way more than just a game. We take this is our pride game."
The home team has won the first three matchups of the season series, and home court could prove even more important if they meet again in the playoffs. Boston eliminated the Cavaliers in the Eastern Conference semifinals last year en route to its NBA-record 17th championship.
The crowd noise at tipoff was reminiscent of last spring's playoffs, but nothing in the first half really excited the fans as much as James' missed dunk with eight minutes left in the first period. Bringing the ball back with for a tomahawk slam, he instead banged it off the back of the rim -- to the delight of the sellout crowd.
The intensity returned in the second when the players went chest-to-chest under the Cavs basket after Davis wrapped up Anderson Varejao to prevent an easy layup. James and Allen began jawing at each other while officials tried to separate them. They were each called for technical fouls, as was Cavs center Zydrunas Ilgauskas.
Davis was called for a flagrant foul and ejected -- exacerbating Boston's problem at power forward. (All seemed to be forgiven later in the third, when Allen fouled James to stop him from an easy basket; James helped Allen up and gave him a friendly tap on the behind.)
After the free throws, James hit a 3-pointer and Williams followed with a fadeaway jumper that cut Boston's seven-point lead to 55-54. Cleveland soon made it 57-all, but Pierce hit a jumper before Allen hit a 3-pointer and then scored on a breakaway, losing the handle of the ball only to have it bounce off James and back into Allen's hands for the reverse layup.
Boston led 68-63 when Pierce hit back-to-back 3-pointers to make it an 11-point game.
- It was the first time in NBA history that two teams leading their divisions by at least 17 games had met.
- Joe Smith, who was traded last summer in the deal that brought Williams to Cleveland, returned after buying out his contract with Oklahoma City and re-signing with the Cavs on Thursday.
- Celtics point guard Rajon Rondo left in the first quarter with a slightly sprained ankle but returned in the second quarter. Cleveland forward Ben Wallace missed his fifth straight game with a broken right fibula.
- Cleveland shot 38 free throws to 12 for Boston.