1903 – New York wins its third doubleheader in a week, clipping St. Louis, 6 – 2 and 9 – 7. Christy Mathewson strikes out 10 in the opener as he outpitches Three-Finger Brown.

This Day In Baseball

On August 13, 1903 — 1903 – New York wins its third doubleheader in a week, clipping St. Louis, 6 – 2 and 9 – 7. Christy Mathewson strikes out 10 in the opener as he outpitches Three-Finger Brown.

Source:
Baseball Reference August 13
National Pastime
Retro Sheet
Hall of Fame
SABR Games Project
Replay The Game