Houston, April 11 (IANS): Kevin Anderson secured a semi-final berth at the US Clay Court tennis championships here after a five-hour rain delay, beating Jeremy Chardy 7-5, 6-7 (6-8), 7-6 (7-3).

The 28-year-old South African didn't wrap up Friday's marathon quarter-final match until 11 hours after he stepped on court to face France's Chardy, reports Xinhua.

American Sam Querrey toppled top seed Feliciano Lopez of Spain 6-4, 6-1, setting up a semi-final clash against another Spaniard Fernando Verdasco, who breezed past the Russian Teimuraz Gabashvili 6-2, 6-3.

Anderson now seeks to reach the 10th Association of Tennis Professionals (ATP) Tour final of his career and his second this season when he faces World No.46 Jack Sock of the United States in his next match. He also made the final earlier this year in Memphis.

Sock outlasted Santiago Giraldo 6-4, 6-4 to reach the last four.

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