The Pirates overcome a 5 – 0 deficit against Christy Mathewson by scoring a run in the 5th and five more in the 6th for a 6 – 5 win.

On May 16, 1904 — The Pirates overcome a 5 – 0 deficit against Christy Mathewson by scoring a run in the 5th and five more in the 6th for a 6 – 5 win.

Source:
Baseball Reference May 16