THE BOSTON Celtics lost Game 1 - and they may have lost their floor leader for Game 2.

Josh Smith scored 22 points and grabbed 18 rebounds as the Atlanta Hawks built a big lead early, then held on for an 83-74 victory over the visiting Celtics in their opener of the Eastern Conference playoffs Sunday night.

But this one will be remembered for what happened in the final minute, not the Hawks' blistering start. While complaining about a call, Boston star Rajon Rondo was ejected for bumping an official and faces a possible suspension when the teams meet again Tuesday night in Atlanta.

"I didn't intentionally chest-bump him, but that's what it appears to be," Rondo said.

The Hawks, who led by as many as 19 in the first half, were clinging to a four-point lead when Rondo lost his cool with 41 seconds remaining. Boston's Brandon Bass was called for a foul on Smith tussling for a loose ball, with both players sprawled on the court out beyond the foul line. Rondo screamed at official Marc Davis, who quickly called a technical. Rondo then bumped Davis with his chest and was tossed out.

A suspension could be coming, too.

Rondo, who scored 20 points and dished 11 assists, clearly appeared to stick out his chest to strike the official. That's a huge no-no and will almost surely draw the wrath of NBA commissioner David Stern.

"It's out of my control," Rondo said. "Obviously, I want to be there for my teammates but other than that, it's out of my control."

Getting in some immediate lobbying, Celtics coach Doc Rivers saw things a bit differently than the replay showed. Not surprisingly, he doesn't think Rondo deserves a suspension.

"I'm always worried, but I would be surprised if that happens," Rivers said. "I thought Rondo was walking toward Marc, and Marc turned back toward him, and that's when Rondo bumped him . . . That's all it was, in my opinion. But we'll see."

Rondo had a similar take.

"Obviously I was upset about the call and I said some words to Marc. I deserved the first tech," Rondo said. "As I was walking, I thought he stopped. My momentum carried me into him. I even think I tripped on his foot."

At the beginning, the Hawks looked much quicker and faster than the aging Celtics. With every starter outside of Jason Collins contributing at least four points, Atlanta raced to a 20-6 lead with the game just over 5 minutes old. The Hawks twice pushed the margin as high as 19 points and settled for a 49-35 edge at halftime.

"We came out like our jerseys were going to win the game, because we're the Celtics," Rivers said. "You've got to play to win the game."

Celtics guard Ray Allen missed a playoff game for the first time in his career because of an ailing right ankle.

In other games * 

At Memphis, Chris Paul hit a pair of free throws with 23.7 seconds left, and the Los Angeles Clippers rallied from 27 down to beat the Memphis Grizzlies, 99-98, in the opening game of the Western Conference series.

Memphis' Rudy Gay missed a 15-footer with 0.9 seconds left after the Grizzlies squandered a lead they held for the first 47 minutes.

* At Los Angeles, Kobe Bryant scored 31 points, Andrew Bynum posted the Lakers' first playoff triple-double in 21 years with an NBA postseason record-tying 10 blocked shots, and LA thoroughly controlled the tempo in a playoff-opening 103-88 victory over the Denver Nuggets.

Bynum, the Lakers' All-Star center coming off his best regular season, also had 10 points and 13 rebounds while incredibly blocking 11 percent of the Nuggets' 90 shots. Game 2 is Tuesday night.

* At San Antonio, Tony Parker scored 28 points and the Spurs won their first playoff opener in 4 years, beating the Utah Jazz, 106-91, in Game 1 of their first-round series.

Tim Duncan added 17 points and 11 rebounds, helping the Spurs dodge another early playoff letdown. Despite boasting the No. 1 seed again, San Antonio hadn't won a Game 1 in its last six postseason series. Game 2 is Wednesday in San Antonio.