SAN FRANCISCO -- Golden State Warriors guard Gary Payton II is expected to miss approximately a month with a fractured left elbow, sources told ESPN's Adrian Wojnarowski on Wednesday. The possibility that Payton could return for the NBA Finals remains, but only if the Warriors advance in the playoffs.

Payton was injured when Dillon Brooks of the Memphis Grizzlies chased him down from behind on a fast-break layup and hit the Warriors guard in the head in the air with 9:08 left in the first quarter of Game 2 on Tuesday. Payton went down hard and remained on the court for several minutes. After officials reviewed the play, Brooks was ejected.

The NBA is investigating the possibility of a suspension for Brooks. A decision is likely to come on Thursday.

"I don't know if it was intentional, but it was dirty," Warriors coach Steve Kerr said. "There is a code. This code that players follow where you never put a guy's season [or] career in jeopardy by taking somebody out in midair and clubbing him across the head, ultimately fracturing Gary's elbow ... He broke the code. Dillon Brooks broke the code."

After bouncing around the league for the past six years, Payton was having a breakout season in Golden State, getting the starting nod through the first two games of the Western Conference semifinals to defend Memphis' Ja Morant.