The Dallas Mavericks overcame a 15-point, fourth-quarter deficit to beat the visiting Memphis Grizzlies 121-116 in the NBA Cup on Tuesday behind Luka Doncic’s 37 points and 12 rebounds and Dereck Lively III’s 17 points and 11 rebounds. The Grizzlies and Mavericks were playing in their final game of the NBA Cup group stage. With