Robinson suffered the injury towards the end of the first half on Friday against the Celtics, though Robinson said via The New York Post’s Stefan Bondy that he might have suffered the initial injury a week prior. He did not start the second half against Boston, briefly came back into the game, and then did not play the entire fourth quarter.

Knicks head coach Tom Thibodeau added after Sunday’s practice that Robinson will be undergoing “additional testing” on his ankle, according to The Athletic’s Fred Katz. He underwent x-rays over the weekend, which came back negative, per The New York Post’s Stefan Bondy.

“I don’t know,” said Thibodeau when asked about the severity of the injury via The Athletic’s Fred Katz. “He’s being examined by the medical people. So until we get the report, it’s just speculation.”

Isaiah Hartenstein will have to fill the void left by Robinson’s absence

Should Robinson, who has played every game this season, miss an extended period of time, Isaiah Hartenstein would slot into the starting five in place of Robinson, with Jericho Sims likely being elevated to the backup center role.

Sims started in 16 games last season when Robinson missed time with an injury. He averaged 4.2 points and 6.3 rebounds in those spot starts.

While not having Robinson, who is averaging a career-high 10.3 rebounds and over a block and a steal per game, would be a major blow to the Knicks, Hartenstein has proven to be capable of filling the void to a degree.

Hartenstein’s 5.6 rebounds on the season rank fourth among all backup centers (minimum 15 games played). He also boasts a 110.0 defensive rating, showcasing his ability to defend the basket at a high level.

There have been several instances since last season where Hartenstein would have to play more minutes if Robinson was in foul trouble, and he was instrumental in the Knicks’ playoff success last year as a secondary option, at times closing games over Robinson.

The Knicks depth will be tested without Robinson

While the starting five won’t suffer many repercussions, the bench unit’s depth will certainly take a hit without Hartenstein.