BOSTON -- Joel Embiid answered the criticism from a couple of Hall of Famers in the most productive way possible.

After Shaquille O'Neal and Charles Barkley said Embiid wasn't playing up to his potential, the 76ers center conceded that they were probably right. Then he produced one of his best games of the season: a season-high 38 points along with 13 rebounds in a 115-109 victory over the Boston Celtics on Thursday night.

"All of the stuff he has been dealing with he handled like an adult, with humility. And he responded in a dramatic way,'' Philadelphia coach Brett Brown said. "He was dominant, was a leader and one of his best games as a Sixer.''

Embiid scored 16 points in the fourth quarter, hitting 5 of 6 free throws in the final 26 seconds after Boston scored seven straight points to erase most of a nine-point deficit. With Philadelphia leading by four in the final 15 seconds, he blocked Daniel Theis' shot to help clinch it.

Earlier in the week, Barkley said Embiid is the toughest matchup in the league, but he doesn't take advantage of it. O'Neal said on the TNT broadcast that Embiid shouldn't settle for 22 points a game, his current average, but should aim for more like 28 or 30.

"I like when I get criticized,'' Embiid said after the game. "For them to say I have the potential to be the best player in the world, and I haven't shown that yet, I need to play harder.''

Celtics center Enes Kanter said he approached Embiid during the game and told him not to worry about the criticism.

"He's one of the best big men in the league,'' said Kanter, who scored a season-high 20 points with nine rebounds. "I told him, 'Hey, don't worry about it.' I told him to just go out and play your game.''

Tobias Harris had 23 points, eight rebounds and seven assists for the Sixers, who won their fourth consecutive game and their eighth in nine tries.

Kemba Walker scored 29 points for Boston, which lost at home for the first time all season. Gordon Hayward scored 19.

LATE RUNS

After helping the Sixers hang around for three quarters, Embiid dragged them to a 106-97 lead with just over two minutes left. Walker hit three free throws, then Kanter scored on a tip-in and Hayward hit a fallaway jumper to make it 106-104 with 61 seconds left.

It was 110-106 when Jayson Tatum made a rainbow 3-pointer over Embiid to make it a one-point game.

But Embiid hit his foul shots, and then gave the 76ers a stop on defense to help them pull two games ahead of rival Boston in the Eastern Conference.

"In the fourth quarter, I haven't been the closer these guys have needed me to be this whole season,'' Embiid said.

EARLY LEAD

Walker scored 12 points in the first quarter, when the Celtics opened an eight-point lead before Philadelphia scored eight in a row to tie it. Boston scored the final six points of the first and the first basket of the second to make it 36-28, but that lead didn't last, either.

It was a three-point game at halftime, then back and forth in the third before the Sixers began to pull away in the fourth.

TIP-INS

Sixers: Former Celtic Al Horford sat out the game with left knee and hamstring injuries. He received a standing ovation when he was shown on the scoreboard, and he acknowledged the crowd with a wave. Horford spent three seasons with Boston before opting out of his contract and signing with Philadelphia as a free agent last summer.

Celtics: Marcus Smart (eye) and Robert Williams (hip) both missed Wednesday's game at Indiana and both were unavailable against the 76ers. ... Hayward missed 13 games with a broken left hand, then got hit in the nose in his second game back, on Wednesday at Indiana. He was back in the starting lineup a night later, playing 37 minutes.

UP NEXT

Sixers: Host the Pelicans on Friday.

Celtics: At Dallas on Wednesday.