NEW YORK - Celtics star Jayson Tatum lost 121-113 to the New York Knicks in the fourth quarter in the fourth quarter in the Eastern Conference semi-finals on Monday night, with no weight on his right leg.

The Celtics just flipped the ball and when Tatum rushed forward to the loose ball, his legs flew out and he fell. After a non-contact injury, he buried his face in a towel, with obvious pain.

Celtics coach Joe Mazzulla has no idea of ​​the extent of the injury and said the All-Star forward will take the MRI exam on Tuesday.

"Obviously, you've been paying attention to someone's health. So it's twofold," Mazzulla said. "We're worried about his health, we're worried about doing better for Game 5 when we return to Boston."

Tatum has been playing a sensational game, 42 points in the fourth quarter with a 2:58 run in the first 28 shots of injury (his highest score in the playoffs).

After leaving the floor, he buried his face in his hands as he buried his face in a tunnel in his wheelchair.

Early in the playoffs, Tatum stood out in the second game against the Orlando Magic of the Celtics, the first missed playoff game of his career, wearing a bone bruise on his right wrist. He has since been playing with protective black wrap around his wrist.

An eight-year veteran, 27-year-old Tatum won his first NBA title last year when he led the Celtics to his 18th title.

Boston led New York by more than 20 points in Games 1 and 2, leading by 14 on Monday night, before the Knicks returned in the second half, within a win in the Eastern Conference Finals for the first time in 25 years.

The series resumed Wednesday night in Boston.

“They will be ready,” Mazura said of his team. "I mean, that's who they are. That's that. It's the dressing room they have and they'll be ready. So you trust the guy's role at a moment like this and you'll have a game at a time."

This report includes information from the Associated Press.