Mary Fowler scored a 95th-minute winner as Manchester City avenged last Sunday's defeat by Arsenal and reached the Women's League Cup final.
In a semi-final played just five days after the Gunners claimed a thrilling 4-3 victory over City in the Women's Super League, Fowler had a second-half penalty saved - but redeemed herself with a late, low strike into the bottom right corner.
The Australia forward had opened the scoring in the 26th minute when she rifled past Daphne van Domselaar, but the visitors were pegged back when Mariona Caldentey converted from the spot 10 minutes after the break.
The semi-final reached a boiling point moments later as Fowler was left with her head in her hands after sending her penalty straight at the Arsenal keeper.
But as the threat of extra time loomed, Fowler ended the night as the hero and City's reward is a meeting with WSL leaders Chelsea in the final on 15 March at at Derby's Pride Park Stadium.
It will be a chance for under-pressure City boss Gareth Taylor to win his first trophy with the club since the League Cup in 2022.
However, their victory was somewhat overshadowed by the absence of the club's top scorer Khadija Shaw.
The Jamaica striker withdrew from the semi-final to "protect her mental well-being" after she was subjected to racist and misogynistic abuse following Sunday's game.