Raptors' Jonas Valanciunas has thumb surgery, to miss at least 4 weeks

Toronto Raptors center Jonas Valanciunas will miss at least four weeks after undergoing surgery on his left thumb, the team announced Thursday.

The surgery was performed at Stanford Medical Center in Palo Alto, California, by Dr. Jeffrey Yao, a specialist in hand, wrist and elbow surgery.

Valanciunas will be in a cast for four weeks, and then his status will be re-evaluated.

Also Thursday, the Raptors listed Kawhi Leonard as questionable for Friday night's game at Portland. Leonard has missed the past two games with a bruised right hip.

Valanciunas' injury occurred in the second quarter of Wednesday's victory over the Golden State Warriors. Valanciunas was posting up Draymond Green when, as he turned to make a move, Green swiped down at the ball and hit him on the hand.

The backup center immediately fell to the ground in agony, then got up holding his hand while in visible pain. A trainer spent time working on Valanciunas along the bench before eventually escorting him to the locker room.

Valanciunas is averaging 12.8 points and 7.2 rebounds per game for the Raptors, who have the best record in the NBA at 23-7.

ESPN's Tim Bontemps contributed to this report.