BOSTON (AP) -- Jason Terry scored Boston's last nine points and the Celtics weathered a strong comeback by the New York Knicks, avoiding a sweep with a 97-90 overtime win on Sunday.
Paul Pierce led the Celtics with 29 points as they forced a fifth game in the series, but it was Terry who provided the finishing touches.
In Game 3, he had been elbowed by J.R. Smith, and the NBA suspended the Knicks guard for Sunday's game.
New York had tied the game 84-84 after trailing by 20 points early in the third quarter. It was 88-all before the Celtics regained control and took the lead for good on a 3-pointer by Terry. Carmelo Anthony, who led the Knicks with 36 points, hit a short jumper, but Terry connected on a 15-footer with 50 seconds remaining for a 93-90 lead.
After Anthony missed a 3-pointer with 21 seconds to go, Terry was fouled and sank both free throws. He added a layup to close out the game.
But the Celtics still have a huge deficit in trying to become the first team to win after trailing a series 3-0.
Game 5 is Wednesday night in New York, where the Knicks can win their first playoff series in 13 years.
Jeff Green scored 26 points for the Celtics and Terry finished with 18.
The Celtics showed renewed energy early after being held below 80 points in each of the first three games. They led 54-35 at halftime and 59-39 three minutes into the third quarter before their recent second-half woes returned. In previous first halves, they scored just 25 points in Game 1 and 23 in Game 2. On Sunday, they were outscored 30-14 in the third quarter and led just 68-65 heading into the fourth.