The New York Knicks may have won on Thursday against their cross town rivals, the Brooklyn Nets, but they also suffered a huge blow, as their best player, Kristaps Porzingis, was forced to leave the game early.

The Latvian international big man reportedly tweaked his knee and went to the locker room after hurting it, as he could not continue with the soreness. He did not return to the game, and will be checked by doctors on Friday, according to ESPN’s Ian Begley.

A series of tests are expected to be done on the injured knee to find out its exact extent, and also to check if there’s any structural damage to it. The Knicks fans could only keep their fingers crossed for now, as their team cannot afford him to miss a significant amount of time, with Tim Hardaway Jr. also sidelined.

Porzingis finished the game with 13 points, two rebounds and four assists in only 17 minutes of action. More updates should surface once the results of the tests are in, and his status for the Knicks game on Saturday against the Oklahoma City Thunder is still up in the air.