Drew Longley gave West Michigan a 1-0 lead in the fourth inning when he homered to left field. Danny Pinero followed up with a single before scoring later in the inning on a David Gonzalez RBI single.
The game remained 2-0 until the eighth inning when Longley doubled and later scored on a RBI single by Cole Bauml.
Bauml led West Michigan with three hits on the night while Longley finished with two.
Starting pitcher Alfred Gutierrez picked up his sixth win on the year, shutting Dayton out over seven innings while allowing five hits and striking out seven. Relief pitcher John Schreiber picked up his third save of the season, allowing one hit and striking out two in the final two innings.
With the victory, West Michigan is now 7-1 to start the second half and 52-23 overall on the season.
West Michigan will next travel to Midland to begin a series against the Great Lakes Loons beginning on Friday at 7:05 p.m.