The Pittsburgh Pirates beat the San Diego Padres, 4 – 3, in a marathon thriller. Pittsburgh ties the game in the bottom of the 9th, 13th, and 16th innings before winning it on a Roberto Clemente home run in the 17th.

On July 15, 1971 The Pittsburgh Pirates beat the San Diego Padres, 4 – 3, in a marathon thriller. Pittsburgh ties the game in the bottom of the 9th, 13th, and 16th innings before winning it on a Roberto Clemente home run in the 17th.

Source
Baseball Reference July 15