Ash Barty's sensational Australian Open run continued on Tuesday night with a straight sets victory over Jessica Pegula in the quarter-finals.
The Aussie is yet to drop a set at the tournament and looked unstoppable in her 6-2 6-0 win that took just over an hour.
Barty's sliced backhand caused Pegula plenty of problems on Rod Laver Arena with former Australian Open winner Jim Courier suggesting it was arguably the best in tennis - even giving Roger Federer a run for his money.
"Ash's slice technique is arguably the best backhand slice technique in the world, period," Courier said during the second set.
"Men's, women's tennis, it doesn't matter. It's spectacular. Roger Federer, if you're back in Switzerland, yeah that's right, I said it buddy. She might be better than yours.
"I'm a fanboy of Ash's backhand slice."
While conceding it's a shot she's used to her advantage over the years, Barty was quick to hose down such a comparison as she remains humble in her hunt for a maiden Australian Open crown.
"That's very kind from Jim. I think everyone's shots are unique. I think obviously Roger has one of the most exceptional slice backhands in the game," Barty said post-match.
"Mine's a long way off that. Absolutely, no stretch of the imagination we are even on the same page at all.
"I love to use my slice, I love to get creative with it, to use it offensively and defensively. Over my career I've learnt it is a weapon for me. I try and use it when I have to.
"Sometimes I try and use it when it's my choice and I can be really, really aggressive with it.
"But being able to use it with variety and have different options has been a massive part of my game through this last couple of years of my career."
Barty will next face Madison Keys in the semi-finals on Thursday night with the American booking her spot in the final four after beating fourth seed Barbora Krejcikova on Tuesday.