17 left in the first quarter in place of starter Al Horford.

With the exception of a white compression sleeve on his right leg, it was hard to tell Porzingis was coming off an injury.

He got into the mix quickly, knocking down a pair of free throws after being fouled by Doncic.

A possession later, the Latvian connected in his first field goal when he dropped on a short jumper over Doncic.

Minutes later he got loose in the paint for a two-handed dunk over Derrick Lively.

On Dallas' next possession, Porzingis was there to swat away Jaden Hardy's layup attempt.

The Celtics pushed the ball up the court and got the ball back to their big man, who calmly buried a 16-footer.

It was part of a 17-5 surge by Boston over the final 5:24 of the quarter that saw Porzingis go 4 for 5 from the field, score 11 points, block two shots and grab three rebounds.

Boston carried a 37-20 lead into the second quarter.