Former finalist Garbine Muguruza has ousted world No.1 Angelique Kerber in a three-set cliffhanger to reach the quarter-finals on a helter skelter day at Wimbledon.

Runner-up in 2015 to Serena Williams, Muguruza rallied from a service break down in the deciding set to score a tenacious 4-6 6-4 6-4 win over the top-seeded German.

The Spaniard was quickly followed into the last eight by five-time champion Venus Williams, who swept past Croatian teenager Ana Konjuh 6-3 6-2 in just 64 minutes.

At 37, Williams is now three wins away from becoming the oldest women’s champion in 49 years of professional tennis history.

The American will face French Open champion Jelena Ostapenko in Tuesday’s quarter-finals after the Latvian posted a thrilling fourth-round win over fourth seed Elena Svitolina.

Svitolina saved seven match points before finally succumbing 6-3 7-6 (8-6) after one hour and 44 minutes.

Ostapenko is the first, first-time major champion to progress to the last eight at the ensuing grand slam since Kim Clijsters made the 2006 Australian Open semi-finals after winning the 2005 US Open.

Muguruza will play dual grand slam champion Kuznetsova after the Russian seventh seed earlier outclassed 2012 finalist Agnieszka Radwanska in straight sets to be the first woman through to the last eight.

A dual grand slam winner, Kuznetsova won 6-2 6-4 in one hour and 31 minutes to qualify for her fourth quarter-final at the All England Club – but first in a decade.

Unseeded Slovak Magdalena Rybarikova is also through after ending the run of Croatian qualifier Petra Martic with a 6-4 2-6 6-3 victory.

Rybarikova awaits the winner of the fourth-round match between fifth seed Caroline Woizniacki and Pat Cashed-coached American Coco Vandeweghe.