Carl Hubbell stop the Braves, 3 – 0, in the opener and Giants pitcher Bill Walker matches the King with a 6 – 0 whitewash in the nitecap.

On May 21, 1931 — Carl Hubbell stop the Braves, 3 – 0, in the opener and Giants pitcher Bill Walker matches the King with a 6 – 0 whitewash in the nitecap.

Source:
Baseball Reference May 21