CHARLESTON: Madison Keys added to her growing reputation as she breezed through her quarterfinal contest at the Family Circle Cup on Friday.

The seventh-seeded 20-year-old blew away fellow American Lauren Davis 6-2, 6-2 in just 73 minutes on the clay courts in Charleston, South Carolina.

Keys routinely pounded serves in excess of 160 kilometers per hour (100 mph) and hit precision ground strokes for winners. She hammered four aces, had just one double fault and broke Davis four times.

“I think I was rushing a little bit at the beginning,” Keys said. “After that I really kind of calmed down and just started playing the right balls, just being a little bit smarter on the court.”

The 21-year-old Davis had stunned top-seeded Canadian star Genie Bouchard in straight sets on Wednesday.

Of the players remaining in the draw none are ranked in the top 10 in the world.

The Australian Open semifinalist Keys’ next opponent, on Saturday, will be Czech qualifier Lucie Hradecka, who upset fourth-seeded former French Open runner-up Sara Errani 6-2, 6-4.

Since reaching the semis in Melbourne, Keys was eliminated early in her only two tournaments, at Indian Wells and Miami.

The start of the clay season has been good for her game.

“It’s been a pretty good week,” she said. “I haven’t had many complaints about how I’ve been playing. I’m not trying to get too high on myself, I’m just trying to keep playing how I’ve been playing.”

The last match of the night saw fifth-seeded Angelique Kerber topple 13th-seeded Irina-Camelia Begu 7-6 (7/3), 7-6 (7/4).

Kerber’s opponent in the semifinals will be third-seeded Andrea Petkovic, who rallied from a first-set loss to down Danka Kovinic 2-6, 6-3, 6-1.

Petkovic defeated the Slovak Jana Cepelova in last year’s final.

Anderson in last four

In Houston, Kevin Anderson survived a five-hour rain delay to clinch a berth in the semifinals of the US Clay Court Championships with a grueling 7-5, 6-7 (6/8), 7-6 (7/3) win over Jeremy Chardy.

The 28-year-old South African didn’t wrap up Friday’s marathon quarterfinal match until 11 hours after he stepped on court to face France’s Chardy.

“They were incredibly tough conditions,” Anderson said. “I could have made it a little easier on myself, but it’s something I can improve on going into the next match.

“I have to give myself credit, I think I did a great job sticking it out.”

Anderson now seeks to reach the 10th ATP Tour final of his career and his second this season when he faces world number 46 Jack Sock, of the US, in the semis. He also made the final earlier this year in Memphis.

Anderson served for the match at 5-4 in the second set before Chardy rallied to win the tiebreaker.

Anderson served for the victory again at 5-3 in the third set, only to get broken for a third time. He would need a deciding tiebreak to seal the match.

Sock followed up his upset victory over second seed Roberto Bautista Agut with a 6-4, 6-4 win over Santiago Giraldo.

It is the third time he has reached the semifinals at an ATP event with each coming on a different surface, comprising the hardcourts in Atlanta, grass in Newport and now clay courts in Houston.

American Sam Querrey defeated top seed Feliciano Lopez 6-4, 6-1 and Fernando Verdasco, of Spain, toppled the Russian Teimuraz Gabashvili 6-2, 6-3.

Querrey blasted seven aces in the 64-minute match as he makes his third appearance in the Houston semifinals.