The Braves and the Cubs tie a major league record, using 14 hurlers in a single game. Each team uses seven pitchers when Chicago beats Atlanta at Wrigley Field, 8-6.

This Day In Baseball

On June 3, 1978 — The Braves and the Cubs tie a major league record, using 14 hurlers in a single game. Each team uses seven pitchers when Chicago beats Atlanta at Wrigley Field, 8-6.

Source
Baseball Reference June 3