Jankovic stun Kvitova

Defending champion and second seed Petra Kvitova crashed out of Wimbledon on Saturday leaving just four of the top 10 women left in the tournament.

The Czech, who was also champion in 2011, lost 3-6, 7-5, 6-4 to veteran campaigner Jelena Jankovic who goes on to play 2012 runner-up Agnieszka Radwanska for a spot in the quarter-finals.

Kvitova's earliest loss at the All England Club since 2009 leaves just Serena Williams, Maria Sharapova, Caroline Wozniacki and Lucie Safarova as the last remaining top 10 seeds going into the second week.

Andy Murray survived a shoulder injury scare to make the Wimbledon last 16 with a 6-2, 6-2, 1-6, 6-1 win over Italy's Andreas Seppi.

Murray, the 2013 champion, required a medical time-out for treatment on his right shoulder after dropping the first game of the fourth set.

But the third seed then reeled off six games in succession to set-up a clash against Croatian giant Ivo Karlovic for a place in the quarter-finals.

Seven-time champion Roger Federer defeated big-serving Australian Sam Groth to reach the last 16.

Second seed Federer clinched a 6-4, 6-4, 6-7 (5/7), 6-2 victory over world number 69 Groth who fired a 147mph ace in the third game -- the second fastest serve in tournament history behind Taylor Dent's 148mph in 2010.

Federer will next face Spanish 20th seed Roberto Bautista Agut for a place in the quarter-finals.

Croatia's Ivo Karlovic became the oldest man in 39 years to reach the last-16 when he beat French 13th seed Jo-Wilfried Tsonga.

The 36-year-old giant fired 41 aces in a 7-6 (7/3), 4-6, 7-6 (7/2), 7-6 (11/9) win. Karlovic is the oldest man to make the fourth round at the All England Club since compatriot Niki Pilic in 1976.

The 23rd seed is also the oldest to reach the last-16 of any of the four Grand Slams since 39-year-old Jimmy Connors at the 1991 US Open.

Dreadlocked German qualifier Dustin Brown was unable to follow his triumph over Rafael Nadal when he slumped to a 6-4, 7-6 (7/3), 4-6, 6-3 defeat to Serbian 22nd seed Viktor Troicki.