Lon Warneke, Cubs mound ace, intentionally walks a batter in the 7th to load the bases and bring up Giants P Roy Parmelee. He hits a grand slam for a 5 – 3 win.

This Day In Baseball

On July 17, 1934 Lon Warneke, Cubs mound ace, intentionally walks a batter in the 7th to load the bases and bring up Giants P Roy Parmelee. He hits a grand slam for a 5 – 3 win.

Source
Baseball Reference July 17