DAVID Bates blasted 121 on his return for Middlewich.
Mike Dawson scored 50, but Irby hung on - just - as John Shepherd (5-50) led the lively Middlewich attack.
Middlewich 2nds reduced Alsager to 53-5 and laid the foundations for a sparkling win.
Alsager made some headway, but were all out for 147 (James Prime 3-29, Alex Gill 2-18), giving Middlewich the chance of a 25-point win which they took with aplomb.
Andy Cole (58) led the way, Gill added 27 and Jamie Williams 21 with Steven Parry finishing things off with two huge sixes, Middlewich 150-3.