Melbourne, Jan 23, 2018 (AFP) - - One unseeded player will make the Australian Open semi-finals Wednesday as Roger Federer zeroes in on a sixth title and Angelique Kerber works to keep alive her hopes of a second.
Giantkillers Chung Hyeon and Tennys Sandgren face off in a last-eight showdown no one expected on Rod Laver Arena, with Federer lining up against old foe Tomas Berdych in the evening.
Kerber, who won the title in 2016, has her work cut out against the impressive Madison Keys, while world number Simona Halep takes on Czech sixth seed Karolina Pliskova.
The 58th-ranked Chung and American No.97 Sandgren have exceeded all expectations with their runs to the quarters, knocking out top names along the way, including Stan Wawrinka and Novak Djokovic.
Korea's Chung, 21, won the pair's only meeting in three sets in the first round in Auckland this month, and has been in superb touch.
But Sandgren is also looking good and his confidence is growing.
"With each match I feel like I'm getting more confidence, sure of the things I'm good at," said the 26-year-old, who is remarkably on his Australian Open debut.
A huge amount is at stake for both -- not only making a maiden Grand Slam semi-final, but potentially facing perhaps the greatest player to grace a court in Federer.
The Swiss great must first get past the tricky Berdych.
The defending champion holds a 19-6 lead over the 19th seed dating back to their first meeting in 2004, and is also 4-0 over him in Melbourne.
"I'm looking forward to play against him. He seems in good shape and I'm happy he's over his back issues that he also had at the end of last year," said Federer, who is targeting a 20th Grand Slam title.
Kerber, the only major winner left in the women's draw, also has plenty on her plate with 17th seed Keys yet to drop a set.
The American is confident but wary of the super-fit German.
"I think she has an ability to cover the court and anticipate like really no one else does," said the 22-year-old, who first reached the semi-finals in Melbourne as a teenager in 2015.
Halep is carrying a painful ankle injury, but determined to put it out of her mind against towering Czech Pliskova, who are both searching for their first major title.
"It is going to be a new match. You never know what's going to happen," Halep said after her tiring run to the last eight.
The Romanian beat the Czech in three sets in their only Grand Slam encounter, on clay in the semi-final at Roland Garros last season.