Timothée Chalamet might be a “Complete Unknown” in theaters … but he certainly wasn’t one at the Knicks game Monday — ’cause Karl-Anthony Towns took some time out of his postgame routine to gift him a jersey!!

The cool scene all unfolded just after KAT and New York beat up the Memphis Grizzlies at Madison Square Garden.

The 29-year-old center walked over to the actor — who had some sweet courtside seats for the contest — stripped off his top, signed it and handed it over. The two then posed for a grip of pictures.

Timmy’s response, of course, should surprise nobody — he’s been a diehard Knicks supporter since he was a kid … even once winning a contest for tickets back before he ever wowed audiences on the silver screen.