Caroline Wozniacki confessed she is still haunted by an Australian Open semi-final loss to Li Na in 2011 after reaching the last four for the first time since that agonising defeat.
Wozniacki progressed beyond the quarter-final stage of the first major of the year for a second time in the early hours of Wednesday morning, beating Carla Suarez Navarro 6-0 6-7 (3-7) 6-2 on Rod Laver Arena.
Elise Mertens stands in the way of the former world number one and a maiden final at Melbourne Park as she eyes an elusive first grand slam title.
Li saved a match point before coming from a set down to beat Wozniacki seven years ago and Wozniacki said that remains the most painful defeat of her career.
"It feels great to be back here in the semi-finals." said the Dane. "It's been a few years. Last time I was in the semi-finals here, I had match point against Li Na and I lost it.
"That's still haunting me till this day, so I'm hoping for a different result this time."
She added: "That's one that really hurt. I've lost from match points up and won from match points down before. That one was a special one."
Jana Fett will know how Wozniacki feels, having led the second seed 5-1 in the final set and had two match points in their round-two clash last week, the WTA Finals champion hauling herself off the ropes to complete a great escape
Wozniacki was taken to a third set by Suarez Navarro after failing to win a match point in the second set and the world number two said being so close to defeat against Fett helped her to see off the Spaniard at in the last eight.
"I think that's one thing that kind of helped me resetting into the third set. I was like, 'You know what, I shouldn't really be here. I still have the chance to play myself into the semi-finals. Just stay positive and go for it'. That's really what I was thinking," said Wozniacki.
"That was a crazy comeback. Now everything that I do is just a plus."