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, while controversy marred Jo-Wilfried Tsonga's defeat at the hands of veteran Ivo Karlovic.
Kvitova, 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.
"I don't know what to say. I'm overwhelmed. I'm so excited. My heart is still pumping," said 30-year-old Jankovic who has reached the last 16 for the fifth time.
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.
"I am very happy. It has been a hot week the first week but thankfully I have had easy matches going through without too many long four or five setters," said Federer.
Federer, chasing an 18th major title, hit 56 winners and 17 aces.
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 and goes on to face either 2013 champion Andy Murray or Italy's Andreas Seppi for a place in the quarter-finals.
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.
However, there was controversy in the match when Karlovic appeared to perform a 'double-hit' on Tsonga's set point in the fourth set.
"I just looked at the umpire. He said no. I said okay, next point," said 2011 semi-finalist Tsonga.
"I don't care, to be honest, because it's too late."
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.
Qualifier Brown joins Lukas Rosol, Steve Darcis and Nick Kyrgios who all lost their next match at Wimbledon after knocking out Nadal over the last four years.
Troicki goes on to face Canada's Vasek Pospisil, who beat British wildcard James Ward 6-4, 3-6, 2-6, 6-3, 8-6, for a place in the quarter-finals.
It is the 29-year-old Serb's first last-16 run at Wimbledon since 2012 and his best performance at a Grand Slam since returning from a 12-month drugs ban in July last year.
Brown came through qualifying at Wimbledon but defeat on Saturday meant a swift return to the daily grind.
US Open champion Marin Cilic took just two games to see off John Isner on Saturday after returning to finish their third round match poised at 10-10 in the final set.
Croatian Cilic, the ninth seed, beat the US 17th seed 7-6 (7/4), 6-7 (6/8), 6-4, 6-7 (4/7), 12-10 on Court One in a match that lasted four hours and 31 minutes in total after it had been suspended late Friday due to bad light.
Cilic sent down 35 aces to Isner's 37 and next faces wildcard Denis Kudla, the last American man in the tournament.
Danish fifth seed Wozniacki reached the last 16 for the fourth time with a comfortable 6-2, 6-2 win over Italy's Camila Giorgi.
The former world number one will face Spain's Garbine Muguruza after the 20th seed shocked 2012 semi-finalist Angelique Kerber 7-6 (14/12), 1-6, 6-2.
Muguruza, who made the French Open quarter-finals this year, saved nine set points in the opener on her way to a first appearance in the second week at Wimbledon.
Romania's Monica Niculescu also made the last 16 for the first time, beating Czech world number 134 Kristyna Plískova 6-3, 7-5.
She will face Switzerland's Timea Bacsinszky who put out 2013 runner-up Sabine Lisicki 6-3, 6-2 to book a spot in the last 16.
Belarus qualifier Olga Govortsova also reached the fourth round for the first time with a 7-6 (7/4), 6-3 over Magdalana Rybarikova and next tackles American 21st seed Madison Keys, a semi-finalist in Australia this year.
Date created : 2015-07-04