The eight RBIs for Grandal matched the franchise record and the career best for the switch-hitting catcher. He also doubled and singled.
Grandal is the first catcher to record multiple eight-RBI games since RBIs became official in 1920, according to ESPN Stats & Information research. He also is the fourth player since 1920 with two career four-hit, eight-RBI games, joining Nelson Cruz, Mookie Betts and Jimmie Foxx.
Jose Abreu added three hits and two RBIs as the White Sox improved to an AL-best 43-23 at home this year. Luis Robert also had three hits and scored three times, and Yoan Moncada extended his hitting streak to 13 games.
The AL Central-leading White Sox improved to 4-0 against the crosstown Cubs, winning the season series for the first time since 2014.
Grandal, 32, had an immediate impact in his first game with the White Sox since he tore a tendon in his left knee July 5 at Minnesota.
He connected for his 15th homer in the third, tying it at 6 with a towering three-run drive to right against Keegan Thompson in the rookie right-hander’s third big league start.
Grandal added a two-run double in the fifth, a single in the seventh and another three-run shot in the eighth. He also threw out Frank Schwindel attempting to steal second in the second.