1985 – In the Mariners’ 11 – 4 win, Seattle’s infield again ties the major-league record for assists with 21 against California. Mark Langston goes all the way for the win.

On August 13, 1985 — 1985 – In the Mariners’ 11 – 4 win, Seattle’s infield again ties the major-league record for assists with 21 against California. Mark Langston goes all the way for the win.

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