OKLAHOMA CITY -- Shai Gilgeous-Alexander scored 39 points, and the Oklahoma City Thunder beat the Dallas Mavericks 118-104 on Tuesday night in an NBA Cup quarterfinal.
Jalen Williams scored 18 points and Isaiah Hartenstein added 10 points and 13 rebounds for the Thunder, who will play Wednesday's Golden State-Houston winner in a semifinal on Saturday in Las Vegas.
Oklahoma City's largest lead was 20 points in a rematch of last season's Western Conference semifinals series that Dallas won 4-2.
The Thunder and their collection of elite perimeter defenders held Luka Doncic to 16 points on 5-for-15 shooting.