Isaiah Thomas scored 27 points and Marcus Smart hit a go-ahead 3-pointer with 47 seconds left as the Celtics held off the New York Knicks, 119-114, in a Christmas matinee at Madison Square Garden.
The Knicks' late 11-2 run wiped away a nine-point Celtics lead. After a Carmelo Anthony layup tied it at 112, Smart, who finished with 15 points off the bench, hit a 3 off a pass from Al Horford as the shot clock wound down to put the Celtics ahead to stay.
On the ensuing Knicks possession, Avery Bradley stole the ball from Carmelo Anthony to help secure the Celtics' fifth victory in their past six games.
Horford had 15 points and Kelly Olynyk 16 for Boston (18-13). Anthony had 29, Derick Rose 25 and Kristaps Porzingis 29 for the Knicks (16-14).