On July 9, 1961 — Sherm Lollar’s 9th-inning pinch-hit grand slam, off Frank Funk, for the White Sox, crushes Cleveland, 7 – 5. It is the 5th pinch slam in the American League this season – two by the Sox – and ties the major league record. The Sox also win the second game, 9 – 8. Over the afternoon 8 home runs are hit.

Source:
Baseball Reference July 9