Josh Smith scored 22 points and grabbed 18 rebounds as the Atlanta Hawks defeated the Boston Celtics 83-74 in game one of their NBA Eastern Conference first-round playoff series. Kevin Garnett and Rajon Rondo each scored 20 points for Boston on Sunday, but Rondo ended the contest under a cloud as he was ejected with 41 seconds remaining when he received two quick technical fouls for his reaction to a loose ball foul call on teammate Brandon Bass. After the first technical, Rondo -- who also handed out 11 assists -- appeared to bump referee Marc Davis from behind with his chest in a move that could earn him a suspension by the NBA. "He might have let his competitive nature get the better of him a little bit," said Atlanta's Smith. Rondo insisted he didn't intentionally make contact with the official. "Obviously I was upset about the call and said some words to Marc," Rondo said. "I deserved the first technical. "As I was walking, I thought he stopped and my momentum carried me into him," Rondo said. "I didn't intentionally chest bump him." Jeff Teague added 15 points and six rebounds for the Hawks and Kirk Hinrich chipped in 12. Garnett shrugged off a slow start to score 18 of his points in the second half as Boston attempted to rally, but the Celtics couldn't get over the hump after trailing by as many as 19. Paul Pierce scored 12 points for Boston on 5-of-19 shooting, and the Celtics were 0-of-11 from three-point range. "We wanted home court advantage for a reason," Smith said of the Hawks' determined start. "We didn't want them to come in here and try to steal game one." The contest was the only Eastern Conference match-up on Sunday. On Monday, the New York Knicks will try to rebound from a 100-67 drubbing on Saturday at the hands of LeBron James and Miami as the Heat host game two. "We've been pretty good at bouncing back," said Knicks coach Mike Woodson. "Hopefully, we'll pick up the pieces from where we screwed things up and hopefully be a better team." Orlando, who scored the last 11 points to steal game one from the Pacers at Indiana, will try to press their advantage in game two on Monday. Eastern Conference top seeds Chicago have until Tuesday to get to grips with the season-ending torn knee ligament suffered by superstar point guard Derrick Rose in their game-one victory over Philadelphia on Saturday. "I think we all feel awful for him," Bulls coach Tom Thibodeau said after his team trained on Sunday. "Derrick's not only a great player, he's a great teammate, he's a great person. But it's not a death sentence. It's not a death sentence for him, it's not a death sentence for our team."