Kevin Anderson battles past Jeremy Chardy to reach Houston semi-finals

Kevin Anderson survived a five-hour rain delay to clinch a place in the semi-finals of the US Clay Court Championships with a gruelling 7-5 6-7 (6-8) 7-6 (7-3) win over Jeremy Chardy.

The 28-year-old South African finally wrapped up Friday's marathon quarter-final 11 hours after he stepped on court to face France's Chardy.

Anderson served for the match at 5-4 in the second set but Chardy rallied to win the tie-breaker.

He then served for the victory again at 5-3 in the third set, only to get broken for a third time, before clinching the win in a deciding tie-break.

"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 will now bid to reach the 10th ATP Tour final of his career and his second this season – after reaching the final in Memphis where he lost to Kei Nishikori - when he faces world No 46 Jack Sock.

American Sock followed up his win over second seed Roberto Bautista Agut with a 6-4 6-4 defeat of Santiago Giraldo of Colombia.

It is the third time he has reached the semi-finals 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 now faces another Spaniard in Fernando Verdasco, who toppled the Russian Teimuraz Gabashvili 6-2 6-3.

Querrey blasted seven aces in the 64-minute match to book his third appearance in the Houston semi-finals.