The Braves sweep a doubleheader from Pittsburgh, 7 – 4 and 6 – 5, to take a half-game lead over the second-place Redlegs.
On June 30, 1957 The Braves sweep a doubleheader from Pittsburgh, 7 – 4 and 6 – 5, to take a half-game lead over the second-place Redlegs.
Source
Baseball Reference June 30