After West Michigan scored two runs in the bottom of the ninth to tie the game 3-3, Dayton won in the eleventh inning when Cassidy Brown scored on a passed ball.
Caps starting pitcher Matt Manning earned a no-decision, tossing five innings while surrendering one run on four hits and striking out 10. Spenser Watkins took the loss for West Michigan, allowing one unearned run on two hits in two innings.
Alex Webb picked up the victory for Dayton, striking out two and walking two in two innings of work. Isaac Paredes had the lone RBI for West Michigan while Danny Woodrow, Daz Cameron and Cole Bauml each had two hits.
West Michigan finishes the season with a 92-47 record, including regular season and postseason play.