Former Swan Valley Stampeder Paul Bonar scored the winner, as the Winnipeg South Blues doubled the Stamps 4-2 on Sunday.
Dylan Reimer scored in the first period for Swan Valley, while Swan River product Jeff Riddell added his first MJHL goal in the second.
Jayson Argue played for for the second straight night, stopping 34/38 shots.
OCN also lost on Sunday, which keeps the Stamps in first place after the weekend, with an 11-6-1 record (23 pts). OCN and Portage both have 22 points, while Dauphin has 20. Neepawa beat the Blizzard, and now sit 5th with 17. Wayway's got 13 points, as most MJHL teams are now roughly 25% through their seasons.