A source told ESPN's Tim MacMahon on Saturday that Irving suffered "just a bruise" from Powell's fall on his foot. Irving has dealt with soreness in that foot throughout the season.
His status for Monday's game in Memphis has yet to be determined, the source said.
The injury occurred after Irving was fouled on a drive to the basket with 3:51 left in the half. As Irving fell to the ground, Powell leaped for the loose ball and took an awkward fall backward, landing on Irving's foot.
Irving was in obvious pain and stayed on the ground for several minutes as concerned teammates gathered around him. He was able to get to his feet and shoot a pair of free throws, but then checked out of the game and headed for the locker room.
The Mavs ruled out his return a short time later.
Irving finished with 11 points on 4-of-6 shooting along with two rebounds and two assists.