On August 6, 1930 — Gene Rye becomes the first player to hit three homers in a single inning when he blasts a solo homer, a three-run shot, and a grand slam in the Waco Cubs’ 18-run eight-inning eruption in their eventual 20-7 Texas League victory over the visiting Beaumont Exporters at Katy Park. The 24 year-old diminutive southpaw-swinging outfielder, called Half Pint by his teammates, will be signed by the Red Sox, spending the first two months of next season with the team before being released when he hits just .179 in 17 games.

Source:
Baseball Reference August 6
National Pastime
Retro Sheet
Hall of Fame
SABR Games Project
Replay The Game