Canadian teenager Bianca Andreescu continued her incredible run at the ASB Classic, with a three sets win over Venus Williams on Friday.
The 18-year-old won 11 games in a row on her way to a 6-7 (1-7) 6-1 6-3 win over Williams in a thrilling quarter-final match in Auckland.
The win comes a day after Andreescu beat top seed Caroline Wozniacki in the second round.
Ranked 152nd, she won three qualifying matches to reach the main draw and will compete in her first WTA semi-final against Taiwanese star Su-Wei Hsieh.
''I believe that anything is possible and tonight I think I did the impossible,'' Andreescu said. ''My goal was only to qualify and maybe get a couple of rounds in, but now I beat a couple of top players so who knows? I believed in myself to the end. I fought, and I really enjoyed myself.''
After being broken in the opening game of the second set, Andreescu found a new gear when she won 11straight games to take control of the match.
Williams attempted a brave comeback in the third set, but it wasn't quite enough.
Defending champion Julia Goerges meets Victoria Kuzmova in the other semi-final.
Goerges beat Canadian Eugenie Bouchard 3-6, 6-3, 7-6 (6), while Kuzmova overcame American teen Amanda Anisimova 6-3, 2-6, 6-4.