On May 18, 1940, the ball was flying well in Brooklyn as the Cardinals blasted five home runs at Ebbets Field on their way to a 6-2 win over the Dodgers. The offensive explosion was led by Johnny Mize and Terry Moore who each knocked two out of the yard, while Ducky Medwick joined the both of them with one big blast. Mize also tripled in the contest.
The 1940 season was quite the year for Mize. He led the National League with a career high 43 round trippers, along with 137 RBIs. Mize finished second in MVP voting to Cincinnati's first baseman Frank McCormick. McCormick did not have the power numbers that Mize had, but he did lead the league in doubles, hits, and at bats, for the club who went onto knock off the Detroit Tigers in the World Series in a classic seven game battle. Mize only exceeded the 137 ribbie mark one time in his career, and that came in 1947 when he wore the uniform of the New York Giants.
Check out the box score here: http://www.baseball-reference.com/boxes/BRO/BRO194005180.shtml