LONDON (Reuters) - Four-times champion Serena Williams dug deep on Monday to book a place in the Wimbledon quarter-finals, seeing off 'golden-set' challenger Yaroslava Shvedova 6-1 2-6 7-5 just in time before the rain came back down at a gloomy All England Club.
Kazakhstan's Shvedova, who became the first player to win a set at a grand slam without dropping a point in the previous round, troubled the American as the dark clouds gathered above Court Two but was undone by a late flurry of pace and power.
Williams, the sixth seed, took just 26 minutes to race to a first set lead. She dominated with her more powerful serve and ground strokes but was made to work much harder from then on as Shvedova found her rhythm.
The American, watched by her sister Venus and her father, went down a break at 4-2 in the second as she started to struggle with her movement.
Shvedova began hitting the lines with a piercing backhand that had Williams flailing and she sealed the set with another screaming effort that sailed past the American.
With Williams's performance so far as temperamental as the British Wimbledon weather, the final set was a much more even contest, both women exchanging blows in lengthening rallies.
Four break points came and went for Williams as Shvedova dug in with some brilliant shots. But the Kazakh was undone by two double faults that put her in trouble and left her 6-5 down.
With light rain now trickling down on court Williams produced a superb lobbed backhand in the final game that had the crowd cheering before a blazing backhand sent Shvedova lunging in vain and sealed victory in just under two hours.
"I felt fine out there I think we both wanted to keep playing because it was so deep into the match," Williams said.
"I'm not tired so I feel good. I feel like I can play so much better than what I have been playing."
Williams, 30, and 13-times grand slam champion, will next face holder Petra Kvitova.
Editing by Pritha Sarkar