Keys, Hradecka surprise semifinalists at the Family Circle

CHARLESTON, S.C. (AP) Madison Keys and Lucie Hradecka are finding their games on clay and are both surprise semifinalists at the Family Circle Cup.

Keys, the seventh seed, put on a dominating show to beat fellow American and one-time training partner Lauren Davis, 6-2, 6-2. Hradecka, a qualifier from the Czech Republic, topped her second seeded player in as many days, knocking out No. 4 seed Sara Errani, 6-2, 6-4.

The two will square off Saturday for a spot in their first championship final of the year.

Third-seeded Andrea Petkovic brought some stability - and as defending champion, a familiar name - into the semifinals with a 2-6, 6-3, 6-1 victory over qualifier Danka Kovinic. Petkovic will try and reach her second straight final here against German countrywoman and good friend in fifth-seeded Angelique Kerber.

Kerber beat 13th seeded Irina-Camelia Begu 7-6 (3), 7-6 (4).

The power-hitting Keys, 20, came into the even with a losing record on clay. Yet, she's lost only nine games her first three matches here this week with a dazzling display of power and poise.

''I haven't really had many complaints about how I've been playing,'' Keys said. ''Not trying to get too high on myself of anything like that. Just really trying to move forward and keep playing how I'm playing.''

That game made her impossible for Davis, 21, to match up with. Keys regularly sent serves in excess of 110 mph toward her opponent and, should the shot have been returned, sent back shots into the corners that appeared even faster.

Clay had been Keys least favorite surface - she was 11-13 on it the previous three years - and even she's a bit stunned at her results. ''It's not the easiest game for me, being on clay,'' she said. ''But so far it's been (a) pretty good transition.''

Hrdecka, ranked 110th coming in this week, had no such concerns about clay courts. Of her 10 trips to semifinals as a professional, nine have come on the slower, softer surface.

This year, Hradecka's has had the added burden of qualifying to get into main draws as she did at Charleston. And Hradecka has taken full advantage of it at the Family Circle. She advanced to the quarterfinals by defeating eight-seed Caroline Garcia on Thursday, then followed that up with an easier than expected win over Errani - the Italian who had the most success on clay of any of the quarterfinalists.

Hradecka rallied from 2-0 with six straight wins to take the first set. When Errani tied things up at four-all in the second set, Hradecka responded by breaking the Italian's serve before closing out things a game later.

Hradecka, who has played six matches in seven days, remembers joking with her coach last Saturday after arriving in Charleston that she hoped they wouldn't be getting off a plane, getting into a car, playing a match and then returning to the airport.

''It's a week later and I'm still here,'' she said, smiling.

For a while, it looked like Petkovic's run of success at the Family Circle might end as Kovinic was up a set and 1-0 in the second set. A frustrated Petkovic slammed her racket down several times early - she said her mother got up and left her seat at the embarrassing tantrums - unable to get a handle on Kovinic's fast serves and relentless ground strokes.

But Petkovic moved closer to the baseline and called on her history - she's 11-0 when taking the court at the Family Circle, her lone misstep coming when she withdrew with injury before her third-round match here in 2013 - to dig her out of the hole.

The 27-year-old German won 10 of the last 12 games to move on.

''Sorry for that racket throwing,'' she told the crowd. ''I've got to work on that.''

Kerber was also frustrated by Begu at the start, trailing 5-1 in the opening set and 5-4 in the second before winning both in tiebreakers.

There'll be different emotions facing Petkovic, a long-time friend who's picked up Kerber's spirits and play when things were not going well.

Still, Kerber said both players will put that past to the side as they compete to reach the finals.

''One of us will win tomorrow and we will try to give our best, and yeah, the better (one) will win tomorrow,'' Kerber said. ''Let's see.''