Golden Square batter Sarah Perry demolished the record books in her side's round five Lisa Chesters Shield clash against White Hills on Sunday.
The Bulldog's first drop flailed the Demon's attack to all parts of Shadforth Park on her way to a BDCA women's cricket record score of 153 not out.
It is only the third century in competition history, with all three being made by Bulldogs batters.
Mannes and Norquay had put together opening partnerships of 84, 24, 80 and 165 in the first month of 2023-24, so the Demons would have sensed a chance when their captain Letesha Bawden trapped Mannes LBW for a second ball duck.
Having been barely needed in the previous fortnight, Perry entered with little time at the crease since her round one score of 76 not out.
In her previous three hits, Perry made scores of five, four and three.
But any lingering worries of poor form or a Demons sniff were quickly extinguished as Perry thrashed 21 boundaries and five maximums in the 96-ball innings.
Not often used to playing the foil, Norquay was still highly impressive as she combined with her record-breaking teammate for an unbeaten 263-run stand, of which she contributed 87 herself from 64 deliveries.
Norquay has made 307 runs at an average of 153.5 so far this season, while Perry's amassed 241 at 120.5.
The reigning premiers total of 1-267 from their 25 overs was never going to be challenged as the Demons crumbled to 9-82.
Melissa Popple (3-8 off 5.0) and Alisha Lourie (3-16 off 5.0) were the pick of the bowlers for the Bulldogs, who will have a chance to break free from the pack with Sandhurst next week when it travels to third-placed Bendigo.
Sandhurst continued its undefeated beginning to the season with a comprehensive nine-wicket victory over Strathfieldsaye.
Having won the toss and electing to bowl, the Dragons threw the ball around with ten players, all sending down at least two overs.
The wickets were shared as six bowlers picked up scalps, with Abby-Lee Scott (2-11 off 3.4) having the best figures as the Jets were rolled for 67.
MacKenzee Porter snared an early breakthrough for the Jets, but the game was quickly over within 9.4 overs as Dragons skipper Kate Shallard hit 50 not out from 39 deliverers.
Bendigo recorded its third win of the campaign to keep touch with the top two, defeating the winless Suns by four wickets.
Needing 118 for victory, the Goers mowed down the total with eight balls remaining.
Kylie Trimble (52 not out) played a steady hand after the Goers had fallen to 3-8 and 5-47 throughout the run chase.
Racheal Flood (18) provided strong support in a match-winning 53-run stand with Trimble.
Earlier, Amy Ryan (3-17 off 3.0), Allira James (2-7 off 4.0) and Zoe Ross (2-15 off 5.0) all picked up multiple wickets for the Goers.
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