Pat McCaw suffered a non-displaced fracture in his left wrist and will be re-evaluated in four weeks, the Warriors announced.
He will be in a cast for 10 days.
The injury took place during Monday night's win over the Suns.
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In the first half against Phoenix, McCaw scored nine points in less than eight minutes of action.
Early in the third quarter, the Warriors announced that McCaw would not return because of a sprained right wrist.
From last Thursday through Monday, the 22-year old played in five games in five nights -- three games with Golden State and two with the Santa Cruz Warriors.
McCaw is averaging 3.7 points, 1.4 rebounds and 1.4 assists in 51 games (six starts) this season.
Golden State Warriors
He is shooting 44 percent overall and 25 percent from 3-point territory.
McCaw will be a restricted free agent this summer.
Drew Shiller is the co-host of Warriors Outsiders. Follow him on Twitter @DrewShiller