Australian Open semi-finalist Danielle Collins freed her mind by standing on the side of a mountain and says her body is also now allowing her to fulfil her tennis potential.

Collins will face Poland's Iga Swiatek in Thursday's final four showdown on Rod Laver Arena after a 7-5 6-1 demolition of French veteran Alize Cornet.

The 30th seed made the final four at Melbourne Park in 2019 in her best grand slam result and was thrilled to be back.

"It feels incredible, especially after some of the health challenges I've had," Collins said.

"To be able to get back to this level and be able to compete like the way I have been, and to be as physical as I have is so rewarding."

The 28-year-old has spoken through the tournament of her successful surgery for endometriosis; a debilitating condition when tissue that normally lines the inside of the uterus grows outside of it.

Before her operation last April Collins was in agonising pain during some tournaments - at one stage forced to serve underarm - while she wasn't able to train at full capacity through the month.

"When you're dealing with that type of physical pain multiple weeks out of the month, you're not putting yourself in a position to be able to perform consistently and to be at your best whether as an athlete or a person," Collins said.

"I think I certainly feel a lot freer - just not having to deal with the symptoms that I used to deal with on a daily basis."

While the surgery changed her life physically, Collins credited a girls weekend away with fellow American player Bethanie Mattek-Sands for also freeing her mind.

The doubles ace took Collins rock-climbing in Arizona, unaware that her friend had a fear of heights and was uncomfortable even being in a tall building.

"We went out and I was terrified," Collins said,

"I think halfway through it I realised every time I step out on the court, it's not life or death but for people in rock climbing, it can be.

"That was a really big realisation for me and something that helped me grow to step out of my comfort zone.

"That was a huge moment of growth for me."