Kristaps Porzingis is trending toward returning for Game 2 of the Eastern Conference semifinals after missing the second half of Game 1 with an illness.

The Celtics will, however, likely be without another core member of their rotation.

Bench sharpshooter Sam Hauser is listed as doubtful for Wednesday’s game at TD Garden after spraining his ankle during Monday’s 108-105 overtime loss to the New York Knicks.

Hauser has been one of the Celtics’ most reliable 3-point threats since becoming a core rotation player last season, making 42.4% of his threes in 2023-24 and a team-best 41.6% this season. He’s been largely silent so far this postseason, though, scoring zero points in four of Boston’s first six games.

The 27-year-old wing was not one of head coach Joe Mazzulla’s preferred reserves in Game 1 against New York, sitting until the third quarter and then suffering his injury four minutes later while fouling Knicks wing OG Anunoby on a 3-point shot.

It was the first time in 175 appearances over the last two seasons that Hauser did not see the floor before halftime. He went 0-for-2 from three and was a minus-7 in his limited action.

As for Porzingis, he exited midway through the second quarter with an illness and did not return despite participating in second-half warmups. Mazzulla revealed Tuesday that his ailment is related to the viral illness that sidelined him for nine games in late February and early March.

“Since he came back, I think he’s been kind of dealing with it on and off, fighting through it, working through it, doing the best that he can,” Mazzulla said. “I think it was just too much for him in that game. I didn’t know that was going to happen until I found out about it in that game. But he had been working through it since he got back, and he’s done a great job of being available. It was just tough for him to continue (Monday), so we’ll see kind of how he handles that.”

Mazzulla described both players as “day to day.”