Celtics injury report: Kristaps Porzingis upgraded for Rockets game Friday

HOUSTON — The Celtics will get some reinforcements back in the lineup Friday night when they face off against the Houston Rockets.

Boston upgraded Kristaps Porzingis (ankle) to available after the big man missed Thursday’s win over the Timberwolves. Al Horford has been declared out for the second half of the back-to-back due to rest. Jaylen Brown (shoulder) will miss his second straight game.

Porzingis had missed the previous four games after suffering a left ankle sprain on Christmas Day against the 76ers. He took part in a shootaround on Thursday morning before being ruled out but said he was feeling much better coming off that workout. He spoke about his frustration about dealing with multiple ankle injuries since his return from offseason surgery last month.

“I’m not going to lie,” Porzingis said Thursday. “It’s super annoying, super frustrating to not be able to catch a good rhythm and already, boom, some small thing happens and you’re out for a couple games. Just to be dealing with this. It’s part of the life we choose. My body is obviously very particular, so these things can happen to me.”

With Horford sitting the tail end of the back-to-back, Porzingis should slot back into his starting center role. He has no minutes restrictions for his return according to Joe Mazzulla. Brown remains day-to-day with a shoulder strain after suffering the injury in the blowout win over the Raptors on Tuesday.

The Rockets will be shorthanded in the frontcourt as well, missing Jabari Smith Jr. (broken hand) and Tari Eason (injury management). The Celtics and Rockets tip off at 8 p.m. Thursday.

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