Keothavong has reached the third WTA Tour semi-final of her career
Anne Keothavong battled through to the semi-finals of the RMK Championships in Memphis with a 6-2 1-6 6-2 victory over New Zealand's Marina Erakovic.
After losing the first two games of the match Keothavong dominated, winning six games in a row to take the first set.
The 25-year-old Londoner's first serve let her down in the second set but she bounced back.
Keothavong went on to win four games in a row in the third set to brush aside Erakovic and reach the semi-finals.
The British number one again showed how far she has progressed as she overpowered the New Zealander, who beat her in straight sets at Surbiton last year, to reach the third WTA Tour semi-final of her career.
Keothavong, who also made the last four in Auckland in January, will face number one seed Caroline Wozniacki in the semi-finals after the Dane's 2-6 6-3 6-3 win over Dutch qualifier Michaella Krajicek.
"I'm pleased to get through another match here in Memphis and be in the semis of a WTA tournament for the second time this year," Keothavong told her website.
"Today's match was a little up and down, the first set was pretty solid from me and then I went walkabout in the second.
"My first serve percentage wasn't good enough in the second set but I still had game points and break points in almost every game.
"There were a few close calls and over-rules from the umpire that didn't go my way but I managed to regroup and was very fired up for the third set where I came up with some good tennis.
"My next match against Wozniacki will be a tough one but I feel ready and will give it my best shot."
In the other side of the draw German sixth seed Sabine Lisicki beat third seed Lucie Safarova from the Czech Republic 6-3 6-4.
Her opponent in the semi-final will be second seed Victoria Azarenka of Belarus, who overcame France's Pauline Parmentier 6-4 6-2.