ATLANTA (AP) -- Al Horford missed most of the season.
Now that he's back, the Atlanta Hawks center wants to keep it going as long as he can.
In his first start since January, Horford scored 19 points, hit Atlanta's final two baskets and came up with a potentially season-saving defensive play that allowed the Hawks to hang on for a frenetic 87-86 victory over Boston in Game 5 of the Eastern Conference playoffs Tuesday night, cutting the Celtics' lead in the series to 3-2.
Game 6 is Thursday night in Boston.
If the Hawks can steal one on the road - and they're nearly back at full strength for the first time in more than three months - the decisive game would be back in Atlanta on Saturday.
"We can be nothing but confident," Horford said. "We know it's going to be a big challenge up there."
It looks a little less daunting with the third member of Atlanta's own Big Three back on the court, leading fast breaks and diving fearlessly on the court for loose balls, not the least bit worried about reinjuring his patched-up pectoral muscle.
In addition to pacing the Hawks in scoring, he grabbed 11 rebounds, dished out three assists, came up with three steals and blocked three shots - all while playing more than 31 minutes, far more than the Hawks intended.
"I didn't expect to play that many at all," he said. "We had an arrangement. It was going to be between 15 and 25."
With the season on the line, Horford and the Hawks couldn't worry about arrangements.
"I just wanted to bring that energy to the team and make sure we gave it all we had," he said.
Boston had a chance to end the series when Rajon Rondo stole Josh Smith's inbounds pass with 10 seconds remaining and raced down the court, looking for the winner. But the point guard got hemmed in along the sideline when Horford jumped out to defend him, which caused Rondo to lose control and fling a desperation pass. Smith knocked it away, the ball rolling harmlessly out of bounds as the horn sounded.
"I cornered myself," Rondo said. "Give Al credit."
A relieved Smith collapsed on the scorer's table as glittery streamers fell from the rafters.
"I feel awful the game ended the way it ended, because I thought Rondo willed us back into the game," Celtics coach Doc Rivers said.
Paul Pierce and Kevin Garnett led the Celtics with 16 points apiece. Rondo had 13 points and 12 assists, and the last of his five steals gave Boston a chance to clinch the series early and get some much-needed rest.
Instead, there's still work to do, and now the Celtics have to cope with a player who spent most of the year rehabbing. Horford tore his left pectoral muscle in January, missing the rest of the regular season and the first three games of the playoffs. But he made a surprise return in Game 4, one of the few bright spots in an embarrassing 101-79 loss that gave the Celtics command of the series.
"We got everybody back at the right time," Atlanta star Joe Johnson said. "We have a chance to do something special."
Smith clearly looked hobbled by a sore knee that kept him out of Game 3, but still managed 13 points and 16 rebounds. Jeff Teague had 16 points, while Johnson and Marvin Williams had 15 apiece, giving Atlanta double-figure scoring from all five starters in a revamped lineup.
"This is the team they thought they were going to start the season with," Rivers said. "They now have it, and we have to deal with it."
In a back-and-forth game, the Celtics tied it at 83 on Ray Allen's 3-pointer from the corner, capping a quick 7-0 run.
The Hawks called time out and set up a play that reclaimed the lead for good. Teague drove into the lane and dumped it off to Horford for an uncontested dunk.
After Garnett missed a jumper in the lane, Johnson ran down the shot clock looking as though he had every intention of shooting. But, at the last possible second, he rifled a pass to Horford coming off the wing. The big center threw up a sort of pseudo-hook with Garnett and Brandon Bass all over him. The ball bounced around the rim before falling through with 1:34 left, giving the Hawks an 87-83 lead.
With less than a minute to go, after misses by Pierce and Horford, Pierce was inexplicably left open for a 3-pointer. He swished it, pulling the Celtics within a point. They wouldn't get another, even with a couple of chances.
Teague missed an open 3 for the Hawks, giving Pierce a look at the go-ahead shot. But his 18-foot jumper with Johnson in his face barely touched the bottom of the net, falling harmlessly out of bounds while Pierce looked around in disbelief, believing he must have been fouled.
Rondo's steal gave the Celtics one more opportunity, but they never got a shot off.
"My heart was racing a hundred miles an hour on that last sequence," Hawks coach Larry Drew said.
Boston appeared to have the momentum when it closed the third quarter on a Rondo-led 10-0 spurt that erased Atlanta's 12-point lead. The Celtics kept it going in the fourth, pushing out to a 73-69 lead on Allen's 3-pointer with 8 1/2 minutes remaining.
But no edge was safe in this topsy-turvy game. The Hawks ripped off a 14-3 run. The Celtics called time out and scored seven straight of their own, with Allen sinking another 3 to tie it up.
In the end, Horford came up with the biggest plays of all.
"He was a superman for us," Drew said.
Welcome back, Al.
Notes: The Hawks have used three different lineups in the five-game series. ... Despite bone spurs, Allen kept up his solid play off the bench with 15 points. Bass added 14. ... With Horford back, former starter Jason Collins played only 10 seconds for Atlanta.
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