Knicks center Mitchell Robinson (23) fights for rebounding position against...

Knicks center Mitchell Robinson (23) fights for rebounding position against Phoenix Suns forwards Yuta Watanabe (18) and Drew Eubanks (14) during the second half of a game on Nov. 26, 2023 at Madison Square Garden. Credit: AP/Peter K. Afriyie

It had to be a shock to Mitchell Robinson to find out that he has a stress fracture in his left ankle and will need surgery that will keep him out at least eight to 10 weeks.

On Friday, after sitting out most of the second half of the Knicks’ loss in Boston, Robinson said he thought the ankle injury was “nothing crazy. I think I took a wrong step, maybe.”

Really wrong. The Knicks announced on Monday that their defensive stalwart will undergo surgery “this week” and will be re-evaluated in eight to 10 weeks.

Robinson had said the injury didn’t even occur on Friday. “It happened like a week ago,” he said after the Boston game. Additional testing over the weekend revealed the stress fracture.

“Tough news for him because he’s worked extremely hard and played really, really well,” coach Tom Thibodeau said before the Knicks beat Toronto, 136-130, at the Garden. “But he’s tough-minded and he’ll bounce back.”

Robinson was averaging 6.2 points, 10.3 rebounds, 1.3 blocks and 1.5 steals in 29.2 minutes per game. His 112 offensive rebounds (5.3 per game) led the NBA.

“It’s hard to replace a player like Mitch individually,” Thibodeau said. “Very hard to do. But collectively we can. We’re capable of playing great team defense. We’ve been an outstanding rebounding team the entire year, so we just have to do it more as a group, and that’s going to be our challenge.”

Robinson’s spot in Monday’s starting lineup was taken by Jericho Sims, who had played a total of 25 minutes all season. The bulk of Robinson’s minutes will go to Isaiah Hartenstein, who has excelled off the bench. Hartenstein went into Monday averaging 5.3 points and 5.6 rebounds in 17.6 minutes per game.

“We’re excited about that position,” Thibodeau said. “We feel that Isaiah has had a terrific season, and when you look at his net rating thus far, it’s really off the charts. And then Jericho, as he did last year, is practicing great

“We have a lot of confidence in his ability and we feel very strongly about what he did last year and also preparing himself for this season. So we feel that we have more than enough. Everyone’s capable of playing great defense and helping the team, and that’s what we’re going to have to do.”

Hartenstein’s net rating was 4.5 going into Monday. Net rating for an individual player measures a team’s point differential per 100 possessions when the player is on the court.

Robinson’s presence is easier to measure because the 7-footer protects the rim and is a top-flight rebounder.

This is not the first time Robinson has suffered a serious injury. The 25-year-old has never played in more than the 72 games he appeared in during the 2021-22 regular season.

Last season, after the Knicks signed Robinson to a four-year, $60 million contract extension, he appeared in 59 of 82 regular-season games and another 11 in his first postseason.

The Knicks did get good news on Monday. Point guard Jalen Brunson, who was listed as questionable, had 21 points and nine assists against Toronto after injuring his left ankle with 21.1 seconds left and the Knicks down by 12 on Friday.

Immanuel Quickley, who Thibodeau said would be a game-time decision, did not play because of right knee inflammation. The Knicks recalled forward Dylan Windler from Westchester of the G League. Windler appeared briefly in three games for the Knicks earlier this season for a total of seven minutes.

SUBSCRIBE

Unlimited Digital AccessOnly 25¢for 6 months

ACT NOWSALE ENDS SOON | CANCEL ANYTIME