Briton Dan Evans reached the Sydney International semi-finals by upsetting top seed Dominic Thiem - his first victory over a top-10 ranked player.
Evans beat the Austrian world number eight 3-6 6-4 6-1 and will now face Russian Andrey Kuznetsov on Friday.
"I just had to hang in there," world number 67 Evans said.
"I knew I'd have to do a lot of running. I had to try to force my game on him, come forward and I did that in the end pretty well."
The British number three will be looking to reach his first Tour final, having only previously reached a semi-final in Zagreb in 2014.
In the men's doubles, Britain's Jamie Murray and Brazilian partner Bruno Soares also reached the semi-finals by beating Florian Mayer and Philipp Petzschner 6-3 6-4.