It took a moment for Dan Yang to register exactly whose fist he had bumped one Sunday afternoon earlier this year.

Mr. Yang, a comedian, was lacing his sneakers before his weekly pickup basketball game, nonchalantly greeting the other players as they entered the gym.

He extended a pound to Ben Marshall, a writer and performer for “Saturday Night Live,” then did the same to a newcomer in a Hawaiian shirt shuffling a few steps behind.

“But I did a double take,” Mr. Yang said, “because it was Adam Sandler.”

Whether he knew it or not, Mr. Sandler had joined these hoopers in their happy place: a musty, subterranean gym where New York’s buzzing comedy scene and pickup basketball underworld collide.

This weekly, invitation-only session, known simply as the Sunday Game, is populated almost entirely by professional funny people from all corners of the comedy landscape — stand-up comedians on their way up, comics past their primes and, as in the case of Mr. Sandler, industry A-listers.