Mitchell Robinson’s postseason over in crushing Knicks injury blow

The already shorthanded Knicks lost another one.

Mitchell Robinson, the backup center with perpetual injury problems, suffered a setback to his surgically repaired left ankle and his playoffs are finished.

The center underwent testing Tuesday afternoon that uncovered a “stress injury” and he’ll be re-evaluated in six to eight weeks, the Knicks announced.

A second surgery is unnecessary, a source said, but he won’t return even if the Knicks advance to the Finals.

“This is so f–ked up dawg like I don’t even know what to say,” Robinson wrote on X after the news broke. “This is not over! I WILL SEEK REVENGE.”

It’s unclear what Robinson was referencing with “REVENGE” but it’s possibly Joel Embiid, who seemed to aggravate the Knicks center’s ankle during a physical battle in Game 3 of the first round.

Without the 7-footer, the Knicks will lean heavily on starter Isaiah Hartenstein, who broke out in the regular season as a top-shelf center and continued that with 14 points in Monday’s Game 1 win over the Pacers.

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Precious Achiuwa will likely replace Robinson as the backup and certainly has experience in that role after filling in for Robinson and injured power forward Julius Randle in the regular season.

It’s a big opportunity for Achiuwa, who played only two the six games of the Philly series and will be a restricted free agent in the summer.

Achiuwa is smaller and quicker than Robinson, giving the Knicks more versatility to defend pick-and-rolls.

However, Robinson’s absence will create a deficit in rim protection and rebounding.

Robinson was the league’s top offensive rebounder before surgery to repair a stress fracture in his ankle in December, which was at least his fourth in-season procedure since joining the Knicks in 2018.

After this season, the 26-year-old has two years and roughly $27 million remaining on his contract.

He’s the longest-tenured Knick.

Third-year center Jericho Sims also is available, but hasn’t played in any of the first seven postseason games.

The Knicks were already down Randle and Bojan Bogdanvovic, who underwent ankle surgery after getting injured in the Philly series.

The circumstances thrust the Knicks starters into extended minutes for Monday’s Game 1 — particularly Josh Hart (48 minutes), Jalen Brunson (44), Donte DiVincenzo (44) and OG Anunoby (42).

The depleted bench was outscored by the Pacers’ reserves, 46-3.

Robinson struggled Monday with just two points and two rebounds in 11 minutes off the bench.

His offensive rebounding would’ve been a valuable weapon against the undersized Pacers, but Robinson would have also been a liability guarding Myles Turner in the pick-and-pop.

Robinson tends to get lost when he has to guard near the perimeter and Turner, who scored 23 points Monday, is a dangerous 3-point threat.

In that regard, Achiuwa, who only played four minutes in the series opener, is theoretically a better fit to get out to Turner and possibly switch on screens.

Even before the setback announcement, the Knicks had ruled out Robinson for Wednesday’s Game 2 due to “injury management” on the left ankle.

A source said he went for tests following Tuesday’s practice in Tarrytown.

In December, Robinson underwent surgery for a stress fracture and missed 50 straight games over roughly three months.

It had been an uphill battle since.

He appeared to aggravate it while banging with Embiid in Game 3 against the Sixers, limped out of the arena in a walking boot and sat Game 4.

The Knicks had termed that injury a “sprained ankle.”

But this setback is much worse.

Robinson had foot surgery in 2021, hand surgery in 2021 and thumb surgery in 2023.