Overcoming a rocky start to the season, the Bunbury Bulldogs have now picked up four wins from eight games.
Playing at PC Payne Park, the home side kicked three goals in the first half before booting one more in the second.
The Collie Eagles were out of their depth, and remained scoreless throughout the clash.
Backed by Charity Ryder (three goals) and Georgia Mahony (one), Bunbury went on to claim a 4.11 (35) to 0.0 (0) victory.
Busselton retained third spot with a resounding 8.7 (55) to 0.0 (0) win over Carey Park on Saturday afternoon.
Ahead by 15 at the main break, the Magpies notched up six unanswered majors in the second half.
Angela Williamson, Susan Isaacson, Beth Beckett, Julie Baker, Kylie Gibbs, and Rennie Sansom starred for winners.
Claudia Elward (two goals) led South Bunbury to a 26-point victory over Harvey-Brunswick-Leschenault at Hands Oval.
With speed and tenacity on their side, the Tigers crushed the Lions 4.11 (35) to 1.3 (9).