Julia Goerges continued her impressive run on clay by brushing aside Russia's Anastasia Pavlyuchenkova 6-4, 6-2 on Friday to set up a Madrid Open semi-final against fourth seed Victoria Azarenka.
The rangy, big-serving German climbed to 27th in the rankings following her win over world number one Caroline Wozniacki in the Stuttgart final last month.
Goerges then followed up by knocking the Dane out in the third round in Madrid on Thursday.
A break of the Pavlyuchenkova serve in the first set and two in the second were enough to put her through to the semi-finals and she sealed victory against the world number 21 on her first match point with a thumping forehand winner down the line.
"The match was probably closer than the scoreline suggests," said Goerges, wearing shocking pink trousers and sporting turquoise-painted nails.
Goerges played Azarenka in the last 16 in Stuttgart and lost the first set 6-4 before the world number five retired with a shoulder injury.
"I'll think about what I didn't do correctly there and I'll try to put that right tomorrow," the German told reporters.
Belarussian Azarenka dropped her first set of the week against unseeded Czech Lucie Safarova before going through 6-3, 3-6, 6-2.
The 21-year-old, who won back-to-back titles in Miami and Marbella earlier this year and prides herself on an aggressive playing style, can climb one place to number four in the rankings if she reaches Sunday's final.
"I am playing well ... so I am just trying to keep going at the same level," said Azarenka.
"I had a really tough beginning of the season with a lot of expectations and pressure but I guess I learned how to deal with that."
Goerges and Azarenka were joined in the last four by Li Na of China, losing finalist at this year's Australian Open.
The sixth seed was not put off by Bethanie Mattek-Sands's striking attire and battled past the unseeded American 6-4, 3-6, 6-4.
Mattek-Sands has been playing her matches here clad in knee-high black socks and with black patches under her eyes, American Football-style.
"The patches actually help a little bit with the glare," said the 26-year-old. "My husband played football and he kind of got me into that.
"I guess it can look a little scary but it's just fun and that's how I am off the court. I like to be outside the box."
Sixteenth-seeded Czech Petra Kvitova completed the semi-final lineup when she came from a set down to beat Dominika Cibulkova of Slovakia 3-6, 6-3, 7-5.