Jimmy Butler had 30 points and nine rebounds and the Chicago Bulls outlasted Boston 106-102 in Game 1 on Sunday on an emotional night for grieving Celtics star Isaiah Thomas.
Playing a day after 22-year-old sister Chyna Thomas was killed in a car accident in their home state of Washington, Thomas led the top-seeded Celtics with 33 points.
Butler scored 23 points in the second half. Bobby Portis finished with 19 for the Bulls.
Al Horford had 19 points, eight assists and seven rebounds for Boston.
Game 2 is Tuesday night in Boston.