PHILADELPHIA (AP) — Al Horford scored the go-ahead basket for Boston late in overtime in a wild Game 3 where the Philadelphia 76ers gave away the basketball and the confetti, leading the Celtics to a 101-98 win on Saturday night.

The Celtics go for the sweep on Monday.

The ending to regulation was about as wild as it gets for both teams. JJ Redick threw away the basketball on an errant pass to no one that was scooped by Terry Rozier who threw to Jaylen Brown for the basket and an 89-87 lead.

Seconds later, Marco Belinelli stunned everyone with a falling 22-footer in front of the 76ers bench as time expired that sent the game into overtime — and confetti mistakenly blasted from the cannon. There was about a seven-minute delay while team employees scrambled to clean up the mess on the court. Some players even scooped up confetti as everyone waited for the start of overtime.

Belinelli opened OT with a 23-footer and Redick followed with a 3 that appeared to take him off the hook.

But the Celtics wouldn’t let them pull away and Horford escaped for a layup with 5.5 seconds that gave Boston a 99-98 lead. Ben Simmons then threw the ball away after a timeout and Horford sealed the win with two free throws.

Jayson Tatum scored 24 points and Rozier had 18.

Joel Embiid had 22 points and 19 rebounds for the Sixers, Redick scored 18 and Simmons 16.

The Celtics, who rallied from a 22-point deficit to beat the 76ers 108-103 in Game 2, can advance to the Eastern Conference finals for the second straight season on Monday.

The highlight came on Belinelli’s shot at the horn that had the Sixers mobbing him in a wild celebration. Confetti Guy — wearing a “Breaking News: I Don’t Care” T-shirt — pushed the button too early and the rectangular pieces were soaring everywhere.

Confetti Guy — who declined to give his name — came over to press row and said the Sixers “better win or I’m done.”

They didn’t.

Horford hit the big shots in the final minute of overtime to silence what had been a rabid crowd. Super Bowl MVP Nick Foles rang the ceremonial bell and whipped the crowd into a frenzy. One fan waved a sign that said “Philly Special 2.0” as a nod to the trick play called that allowed Foles to catch a touchdown pass against the New England Patriots.

But not every Philly team can beat one from New England in a big game.

Simmons, the rookie of the year favorite, had a miserable Game 2 and scored only one point and failed to score a field goal for the first time all year. Hall of Famer Allen Iverson called Simmons and gave him a needed pick-me-up.

“Just play the game I’ve been playing,” Simmons said AI told him. “I know how to play the game. I can’t think about it too much. I’ve just got to go out there and do it.”

Determined not to get embarrassed again, Simmons scored on a driving layup less than a minute into the game.

“My goal isn’t to go out there and drop 30 every game,” Simmons said. “My goal is to go out there and facilitate and get the best shots we can.”

He did it all in the second quarter when the Sixers looked every bit the team that ended the season on a 16-game win streak.

Trailing by 10 early in the second, Simmons had an emphatic slam to kickstart a rally. Simmons would make the highlight reel with a behind-the-back pass to a charging Embiid for a thunderous dunk over Aron Baynes. Embiid made the free throw and the crowd was going bonkers.

Redick and Dario Saric each hit 3s during the 13-0 run that helped the Sixers take a 51-48 lead into halftime.

TIP-INS

76ers: The Sixers have suddenly become one of the hottest teams at attracting celebrities. Rapper Meek Mill, Questlove of The Roots, celebrity physician Dr. Oz, UFC President Dana White and director M. Night Shyamalan were all at the game, as were other members of the Eagles.

Celtics: The Celtics missed 15 of 22 3s in the first half and only attempted four free throws.

BALL HAWK

Coach Brett Brown endorsed assistant coach Lloyd Pierce as the next head coach of the Atlanta Hawks. Pierce interviewed for the job on Friday.

“It’s a no-brainer. I would hire Lloyd Pierce yesterday,” Brown said.

UP NEXT

Game 4 is Monday at the only-in-the-postseason tip time of 6 p.m. EDT

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