Celtics guard Anfernee Simons (left) drives to the basket against 76ers center Joel Embiid during Friday night's NBA Cup matchup in Philadelphia Friday night.
Celtics guard Anfernee Simons (left) drives to the basket against 76ers center Joel Embiid during Friday night's NBA Cup matchup in Philadelphia Friday night.Chris Szagola/Associated Press
PHILADELPHIA — After the Celtics roared to a 24-point lead against the 76ers on Friday, there were times that they stumbled and wobbled, and there were times it looked like it would turn into a disheartening night rather than an encouraging one.
They gave up all of that massive advantage, as well as most of a 10-point lead in the final minutes. But in the end, Joel Embiid’s potential game-winning 3-pointer at the buzzer was off, and the Celtics escaped with a 109-108 win, their third in a row, in this NBA Cup round robin game.
Jaylen Brown had 32 points to lead the Celtics (3-3) and Anfernee Simons added 19 off the bench. Tyrese Maxey had 26 to lead the previously unbeaten 76ers (4-1), who were undone by 18 turnovers.
After the 76ers roared back from a 64-40 deficit to tie it, 72-72, in the third quarter, the Celtics kept their composure and regained their lead thanks to timely offensive rebounding and strong defense. Boston led, 108-98, with 3:11 left when the 76ers made a final push.
A Quentin Grimes layup was followed by consecutive 3-pointers by Tyrese Maxey and VJ Edgecombe, slicing the deficit to 108-106 with 51.4 seconds to play. Brown was fouled but hit just one of two free throws, and at the other end Maxey converted a quick layup with 20.8 seconds left, making it 109-108.
After a timeout, the inbounds pass went to Payton Pritchard in the backcourt. He may have been anticipating a foul, but the 76ers brought an aggressive trap near the sideline instead, forcing another timeout.
This time the pass came to Brown near midcourt, but the ball was knocked away and Brown was whistled for a foul during the chase for the loose ball with 11.6 seconds left.
Maxey raced toward the hoop and had a good look at a floater over Xavier Tillman, but it caromed off the back rim and Josh Minott grabbed the rebound and was fouled with 3.8 seconds left. He missed both free throws, however, and the 76ers called timeout with 3.5 seconds to play.
The pass came to Grimes in the backcourt, and he was bottled up at the top of the key before finding Embiid at the right arc. The former MVP put up a 3-pointer just before time expired, and it thudded off the back rim, allowing the Celtics to survive.
The Celtics’ suddenly explosive offense kept rolling in the first half Friday, with Brown and Pritchard leading the way at the start. The duo combined to score the Celtics’ first 19 points, but the manner in which they attacked was slightly unusual.
They started 9 for 11 from the field, with just one 3-pointer and one layup in the spree. The rest were mid-range jumpers. Brown is a threat to score in myriad ways, so there is often space for a quick-rise jumper. Pritchard, meanwhile, has an uncanny ability to use his body and create space for these short shots. If he were bigger, some of these plays would probably result in offensive foul calls, but he is not.
Simons came off the bench and was the third Celtic to enter the scoring column, and that was the start of a powerful 14-point first half for him. The Celtics reentered familiar territory by hitting four 3-pointers over the final four minutes of the quarter and took a 38-25 lead to the second.
At the other end, they bothered the 76ers with their speed and full-court pressure, with big man Joel Embiid growing visibly frustrated as he tried rumbling to the basket with no real path.
During one sequence midway through the quarter he pushed toward the hoop for a dunk attempt but lost the ball as he went up. Either frustrated with himself or the lack of a foul call, he stayed back to sulk, and the Celtics wasted no time utilizing the 5-on-4 advantage and finding Simons for a 3-pointer that made it 55-35.
Boston stretched its lead to 24 with just 3:30 left, but its inability to close the quarter authoritatively left an opening for Philadelphia. Rookie VJ Edgecombe, a star of the 76ers’ opening night win at TD Garden, hit a 3-pointer and converted a 3-point play in quick succession. Then the 76ers got an unlikely offensive lift from Andre Drummond, who hit a pair of free throws and drained a 3-pointer from the left corner, just the 19th of his 14-year career. That surge helped the 76ers pull within 68-57 at the break, a manageable deficit.
Embiid gave the 76ers a jolt to start the third. He hit a jumper, converted a layup, and stomped upcourt for a chase-down block that delighted the crowd. An Embiid 3-point play followed by a Maxey runner with 6:41 left tied the score at 72 and capped a 32-8 surge.
The Celtics pushed back in front thanks to timely and aggressive work on the offensive glass. One by Pritchard led to a Brown 3-pointer that pushed Boston back in front. In the quarter the Celtics grabbed six offensive rebounds in the quarter and had a 7-0 edge in second-chance points.
With Maxey and Embiid on the bench late in the quarter the 76ers’ offense stumbled, and Boston took an 89-82 lead to the fourth.
Coach Joe Mazzulla once again leaned on rookie Hugo González to provide a defensive spark, and he seemed to be everywhere during this game. He scrapped for two steals during one 30-second sequence, with the second leading to a White basket that made it 96-87.
Adam Himmelsbach can be reached at adam.himmelsbach@globe.com. Follow him @adamhimmelsbach.