Sammy Sosa’s grand slam and run-scoring double against the Rockies give the Cubs’ slugger 14 RBIs over two games, establishing a new National League record. The previous mark was 13, shared by Nate Colbert (Padres-1972) and Mark Whiten (Cardinals-1993).

On August 11, 2002 — Sammy Sosa’s grand slam and run-scoring double against the Rockies give the Cubs’ slugger 14 RBIs over two games, establishing a new National League record. The previous mark was 13, shared by Nate Colbert (Padres-1972) and Mark Whiten (Cardinals-1993).

Source:
Baseball Reference August 11
National Pastime
Retro Sheet
Hall of Fame
SABR Games Project
Replay The Game