BOSTON -- The Atlanta Hawks have improved since losing to the Celtics in the first round of the playoffs last spring. Too bad for them that the defending champions haven't changed much at all.
NBA finals MVP Paul Pierce hit a fallaway jumper with 0.5 seconds left to give Boston a 103-102 victory over Atlanta on Wednesday night, handing the Hawks their first loss of the season and their first since the Celtics ousted them en route to their unprecedented 17th title.
• The Celtics trailed by as many as 16 points in the second quarter but rallied to win their sixth straight game and eight of nine this season.
• Atlanta lost its first of the season and has now lost four straight games against Boston.
• Paul Pierce scored 23 of his 34 points in the second half, hitting 15 of 16 free throws in the game.
-- ESPN research
"A great player hit a great shot," Hawks coach Mike Woodson said. "I hate for the game to end -- not like that. That game was played beautifully on both ends of the floor, by both teams, and they made a great play at the end."
Pierce scored 34 points in all, Kevin Garnett had 25 with 12 rebounds and Rajon Rondo had 10 assists for the Celtics. Joe Johnson scored 28 for Atlanta, finding an open Marvin Williams for the go-ahead 3-pointer with 7.4 seconds left before Pierce answered at the other end, faking out a pair of defenders and sinking the game-winner.
"The last play was drawn up: Get the ball to Pierce; get the hell out the way," Garnett said. "Superman's in the booth. Let's go home. That was the play, and if you don't believe that ask Doc Rivers and he'll say the same exact thing."
The Celtics beat Atlanta in Boston for the eighth straight time, including all four in their first-round playoff series last spring when they took advantage of the home-court advantage to oust the Hawks in seven games. But Atlanta came in with a perfect 6-0 record and the hopes of making a statement.
"I think we've grown a lot since last season, thanks to the Celtics," Woodson said. "They put us in that mode, that frame of mind, that you've got to come out every night and dig in and play."
Ray Allen scored 17 points, eight of them during an 18-2 run in the second quarter that turned a 44-28 deficit into a tie game at halftime. There were 12 lead changes in the third quarter, and the Celtics never led by as many as two baskets until Garnett hit a jumper from the top of the key, then grabbed a pair of rebounds before laying in an alley-oop that made it 92-88 with 3:33 to play.
Boston still led by four when Johnson hit a pair of free throws and then made a fallaway jumper from just outside the lane to tie it 99-all with 35 seconds left.
Pierce picked up a foul by driving to the basket and made two free throws, then Johnson drove and kicked it out to Williams for a 3-pointer from the right side to give Atlanta a 102-101 lead.
Then came Pierce.
"I sort of got to my sweet spot and I felt good the whole time," he said. "We're playing a lot of playoff teams early, so it's good for us to get close games. ... We're learning from them."
Williams' inbounds pass went through Mike Bibby's hands as time expired.
The Hawks led the entire first quarter, and took a 31-24 advantage when Flip Murray hit a 3-pointer at the buzzer. They scored eight straight points to make it 44-28 with 7:07 left in the half before Boston tied it at 46-all.
"Our team swagger is really high right now," Hawks forward Al Horford said. "We just want to play the game the right way, let people know we're serious."
Last season, Atlanta took its first loss in its second game and didn't win its sixth until Nov. 28, the 14th game of the season. The Hawks started 11-0 in 1997-98. ... Murray had 12 points in the first half off the bench. ... Zaza Pachulia, who replaced Josh Smith in the lineup after he sprained his left ankle Friday night against Toronto, injured his left shoulder and left the game. ... Williams, who made one 3-pointer all last season, had four on Wednesday and is 8-for-11 this season.