BOSTON -- Isaiah Thomas developed a reputation in Boston for big performances late in games. It's quickly becoming apparent that the Celtics probably have an even more potent scoring weapon in Kyrie Irving.
The star guard scored 36 points and Boston held off the weary and short-handed Philadelphia 76ers 108-97 on Thursday night to improve the NBA's best record to 19-4.
It was Irving's fifth game this season with 30 or more points. Al Horford added 21 points and eight rebounds, and Marcus Morris had 17 points as the Celtics bounced back from Monday night's home loss to Detroit with their ninth victory in 11 games.
"It's go time, man," Irving said of his mindset in the fourth quarter. "Especially when the game is in the balance. It's the best time to play. It's just ultimate freedom."
Boston led by five at the end of the third quarter but started the fourth by connecting on seven of its first 11 shots to increase the margin to 95-82. Irving had nine points in the final 12 minutes.
"It's a luxury. Not a lot of teams have that," Horford said of Irving's ability to take over games. "His will to win and make those shots when we need them most -- it just keeps impressing me game by game."
"Kyrie is obviously amazing," Redick said. "Horford doesn't get enough credit for how good he is offensively. As good as Kyrie is, Horford is the hub of everything they do."
It was the third game in four nights for the 76ers, who have lost two of three. Saturday's game against Detroit will conclude a week featuring matchups with the East's three top teams.
Philadelphia played without center Joel Embiid, who continues to rest on the second night of back-to-backs.
With Embiid out, Celtics coach Brad Stevens went with a bigger lineup, starting Aron Baynes in place of Morris.
Philadelphia was able to keep the game tight by knocking down 16 3-pointers.
76ers: A night after taking 29 free throws, an NBA rookie record, Simmons went to the line only four times. ... Embiid, Markelle Fultz (right shoulder soreness), T.J. McConnell (sprained AC joint, left shoulder) and Jahlil Okafor (individualized training) were not with the team.
Celtics: Marcus Smart left in the fourth quarter with pain in his right ankle. He got treatment in the locker room and said afterward that it was feeling better. ... Irving had five of Boston's 12 3-pointers. ... Boston outscored Philadelphia 44-36 in the paint.
"He's certainly one of the most gifted scorers in the game. He can do things just with a tiny amount of space and make it look easy." -- Stevens on Irving.
The Celtics ended the second quarter on an 11-3 run and took a 54-44 lead into halftime. Boston shot 48 percent from the field and was 7 of 16 from beyond the 3-point line.
Philadelphia erased a 12-point deficit and took a 67-65 lead in the third quarter, but Boston got hot again, ending that period on an 11-4 run that included six points by Morris.
The Sixers have already played some of the league's top teams just 21 games into the season. Thursday was their second meeting with the Celtics, and they've also played Golden State and Houston twice, and Cleveland.
But coach Brett Brown is thankful for the tough road they've plodded thus far.
"We're playing NBA royalty right now," Brown said. "We're playing against the league's best. The analytics people tell us we've had the most difficult schedule to date in the NBA, and it feels like that. But I think it expedites learning. ... You're always learning from All-Stars."
76ers: Begin a three-game homestand Saturday against the Detroit Pistons.
Celtics: Continue their five-game homestand Saturday against the Phoenix Suns.
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