Belgium have continued their giant-killing spree to march into the United Cup semi-finals in Sydney with a 2-0 elimination of Czechia.
Elise Mertens clinched the team's last-four spot with an epic three-set win over dual grand slam winner Barbora Krejcikova after Zizou Bergs beat Jakub Mensik in the men's singles match.
Mertens' 5-7 6-1 7-5 comeback win stretched more than two and a half hours at Ken Rosewall Arena.
Krejcikova was left to lament coughing up 10 double-faults as Mertens cashed in to vault Belgium into a showdown on Saturday with Switzerland for a surprise spot in Sunday's final.
"Of course she's a very experienced player, a great player, so I had to adjust my game a little bit," a relieved Mertens said.
"I felt like I had to play more aggressively. She's not giving away any points.
"But I'm very happy with the way I turned it around. I'm very happy with the win. Very happy that I could close it out with my serve."
Bergs had struck the first blow of the night for Belgium, downing the higher-ranked Mensik 6-2 7-6 (7-4).
Australia and Poland will clash in the last quarter-final on Friday night, with the winners to face defending champions the USA.
Maya Joint will open the tie against Poland's six-time grand slam champion Iga Swiatek before world No.6 Alex de Minaur takes on Hubert Hurkacz.
