Sweeting hit a clutch runback with her final stone to improve to 9-0 at the women's national curling championship.
"It wasn't the best throw, I'm not going to lie," she said. "It was a little crafty. But the girls held it so well and they're just such good sweepers that I knew it'd be close."
The victory in a rematch of last year's Scotties final gave Sweeting a berth in the one-two Page Playoff game Friday night against Manitoba's Jennifer Jones, who locked up her spot with a pair of victories.
"We just have to stay strong now," Sweeting said. "Momentum is good going into the playoffs. We just want to finish strong and hopefully just come out on top."
Sweeting and Jones (9-1) will play twice on Friday. They'll meet in the round-robin finale in the morning with the winner to earn the first seed.
"I think you just go hard twice," said Jones, who won Olympic gold last year in Sochi. "You never want to let up (with) anything. We just want to go out there and play our very best."
Homan, the two-time defending champion, fell to 6-3 with the loss. The Ottawa skip was tied in third place with Saskatchewan's Stefanie Lawton, who dumped New Brunswick's Sylvie Robichaud 9-4.
Northern Ontario's Tracy Horgan (6-4) and Ontario's Julie Hastings (5-5) were the only other teams that had a chance at the playoffs entering Thursday night's draw. The top four teams at the end of round-robin play will advance.
Horgan beat Ontario 9-7 before dropping a 6-3 decision to Jones in the afternoon to sit in fifth place. Jones beat Prince Edward Island's Suzanne Birt 10-3 earlier in the day.
Hastings, meanwhile, rebounded from her morning loss by topping Birt 8-6. The Ontario skip was alone in sixth place and clinging to a slim chance of qualifying for a tiebreaker.
Birt, Heather Strong of Newfoundland and Labrador and Nova Scotia's Mary-Anne Arsenault were all eliminated from playoff contention at 4-6. New Brunswick was 10th in the 12-team field at 2-7.
Quebec's Lauren Mann was next at 2-8 and B.C.'s Patti Knezevic was last at 1-9.
Regardless of the results in the last two draws, B.C. will finish last in the round robin as Quebec and New Brunswick both hold the tiebreaker advantage. As a result, B.C. will fall into the qualification round at the 2016 Scotties in Grande Prairie, Alta.
The Yukon and the Northwest Territories were eliminated in this year's qualifier and will round out next year's qualifier field with Nunavut, if that territory decides to participate.
Northern Ontario won this year's qualifier to claim the last spot in the main draw.
The loser of the one-two Page Playoff game will play the winner of Saturday's three-four Page Playoff game in the semifinal on Saturday afternoon. The winner of the one-two game advances straight to Sunday night's final.
The winner of the Scotties will represent Canada at the March 14-22 world women's curling championship in Sapporo, Japan.
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