On July 9, 1971 The A’s beat the Angels, 1 – 0, in the longest shutout in American League history – 20 innings. Vida Blue strikes out 17 batters in 11 innings for the A’s, while the Angels’ Billy Cowanties a major-league record by fanning six times. Both teams combine for 43 strikeouts, a new major-league record for incompetence (or pitching dominance, depending on one’s perspective).

Source:

Baseball Reference July 9