updated 12:32 a.m. ET May 3, 2008

ATLANTA - As streamers poured from the rafters at Philips Arena, Marvin Williams stood at center court with arms folded, looking defiant, even with a sore knee. Zaza Pachulia grabbed a microphone and summed up this improbable series.

“We’re going to Game 7! Woooooooooo!” Pachulia screamed.

Game 7, indeed.

Who would have believed it?

Refusing to let go of their first trip to the playoffs in nine years, the Hawks forced an improbable deciding game with the Boston Celtics when Joe Johnson hit a crucial 3-pointer with 1:07 remaining and Atlanta held on for a 103-100 victory Friday night.

The Hawks, just 37-45 during the regular season, have now beaten the Celtics three times in the space of a week to set up a deciding game in a series that was supposed to be a sweep. After all, Boston went an NBA-leading 66-16 and defeated Atlanta in all three meetings before the playoffs.

But, against all odds, the Hawks are heading to Boston for Game 7 on Sunday.

“Seven! Seven! Seven!” chanted the record crowd of 20,425 at Philips Arena.

The Celtics are still the obvious favorite, having won all three games at their place by an average of 22 points. But the Hawks have lasted longer than anyone would have expected.

“I feel very good,” said Pachulia, a little-used center who’s making quite an impact in this series. “You’ve got to be able to win on the road. We’ve lost three in a row. We should be able to win one up there. It would be sad if we lost four in a row.”

The Celtics looked as shell-shocked as anyone. Paul Pierce fouled out and spent the final minutes on the bench with a towel draped over his head, barely able to watch.

“It’s definitely a dream,” Atlanta’s Josh Smith said. “But we weren’t going to be satisfied with just making the playoffs.”

Williams led the Hawks with 18 points despite missing much of the fourth quarter with a sprained left knee. Kevin Garnett had 22 for the Celtics and Ray Allen added 20, but Pierce — the other member of Boston’s Big Three — fouled out on a disputed call with 4:44 remaining.

The Celtics had a chance after pounding the boards for five chances on one possession before Kendrick Perkins was hacked by Al Horford. Perkins made both free throws with 1:32 left to pull Boston within 97-95.

Johnson, who went to the final period with just seven points on 3-of-9 shooting, came alive in the fourth. He saved his biggest shot for the end, getting James Posey in the air with a pump fake before hitting Atlanta’s only 3-pointer of the game to make it 100-95.

“I took a few dribbles,” Johnson said. “I just wanted to get a good look. I felt like it would go in when it left my hand.”

Posey got Johnson back by making a tough 3 from the wing with 48 seconds left, and the Celtics had a chance when Johnson missed a runner in the lane.

Wanting to finish off the pesky Hawks, the Celtics drew up a play to give Allen a look from beyond the arc. He missed, though; Johnson grabbed the rebound, was fouled and hit two free throws with 10.6 seconds left.

After a quick basket by Garnett, Mike Bibby made only one of two free throws with 7.4 seconds to go, giving the Celtics a shot at forcing overtime. But the Hawks kept the ball from Allen and Posey, forcing Rajon Rondo to launch a long 3 that didn’t even hit the rim as the horn sounded.

Video   Hawks bring count to 3-3 May 2: The Hawks and Celtics prepare for Game 7 in the first round of the NBA playoffs. NBC Sports

For the third time in the series, streamers poured from the Philips Arena rafters.

“I’ve played 13 years, and I’ve been here every year for 13 years,” Garnett said. “This is the first time I’ve seen this atmosphere like this (in Atlanta). That’s the intensity of the playoffs.”

But the Celtics worked all season to get the home-court advantage throughout the playoffs.

Next up, Game 7 in Beantown.

“Our confidence is definitely not shaken,” Garnett insisted.

Pierce has apparently seen enough of Atlanta. He had already cleared out of the locker room by the time reporters were let him. The only thing left behind was a banana peel.

“We put ourselves in this situation,” Posey said. “For one of these teams, it’s going to be their last game. Just expect anything and everything.”

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