Emma Woods scored the game-winning goal with 7:29 left in overtime, giving the Sixers a 3-2 victory over the Connecticut Whales on Saturday to secure Game 2 of their Isobel Cup semifinal series.
Brittany Howard scored twice in the Sixers.
Taylor Gillard scored a goal and an assist, and Kennedy Marchment responded for the Whales.
Toronto entered the game after losing the series opener 5-3 on Friday.
Game 3 is scheduled for Monday to determine the series winner and a spot in the Finals.