London -Seven-time champion Roger Federer defeated big-serving Australian Sam Groth to reach the Wimbledon last 16 on Saturday while Dustin Brown, the conqueror of Rafael Nadal returned to earth with a bump.
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.
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.
"Now we are looking ahead and there are only big matches."
Dreadlocked German qualifier Brown was unable to follow his triumph over Nadal when he slumped to a 6-4, 7-6 (7/3), 4-6, 6-3 defeat to Serbian 22nd seed Viktor Troicki.
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 either British wildcard James Ward or Canada's Vasek Pospisil 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.
"The schedule is to go to the airport and take the earliest flight, because tomorrow morning, I have club matches in Cologne, Germany," said the 30-year-old.
US Open champion Marin Cilic took just two games to see off John Isner on Saturday after returning to finish off their third round match poised at 10-10 in the final set.
- First timers -
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.
"I was playing yesterday really good and I was close to finishing it off. I think throughout all the match I was the one who was putting more pressure on the returns," Cilic said after winning on a fifth match point having had a first match point in the 12th game of the decider on Friday.
Cilic sent down 35 aces to Isner's 37 and next faces wildcard Denis Kudla, the last American man in the tournament, for a place in the quarter-finals.
Danish fifth seed Caroline Wozniacki reached the last 16 for the fourth time with a comfortable 6-2, 6-2 win over Italy's Camila Giorgi.
"I was very happy to win this one. I know that Camila is such a tricky opponent. She hits so hard. I was just trying to get every ball back. I was really pleased how I managed to keep my composure," said Wozniacki.
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 Plskova 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 for the first time.
Marin Cilic (CRO x9) bt John Isner (USA x17) 7-6 (7/4), 6-7 (6/8), 6-4, 6-7 (4/7), 12-10
Viktor Troicki (SRB x22) bt Dustin Brown (GER) 6-4, 7-6 (7/3), 4-6, 6-3
Ivo Karlovic (CRO) bt Jo-Wilfried Tsonga (FRA) 7-6 (7/3), 4-6, 7-6 (7/2), 7-6 (11/9)
Roberto Bautista Agut (ESP x20) bt Nikoloz Basilashvili (GEO) 7-6 (7/4), 6-0, 6-1
Roger Federer (SUI x2) bt Sam Groth (AUS) 6-4, 6-4, 6-7 (5/7), 6-2
Caroline Wozniacki (DEN x5) bt Camila Giorgi (ITA x31) 6-2, 6-2
Garbie Muguruza (ESP x20) bt Angelique Kerber (GER x10) 7-6 (14/12), 1-6, 6-2
Timea Bacsinszky (SUI x15) bt Sabine Lisicki (GER x18) 6-3, 6-2
Monica Niculescu (ROM) bt Kristyna Pliskova (CZE) 6-3, 7-5
Olga Govortsova (BLR) bt Magdalena Rybarikova (SVK) 7-6 (7/4), 6-3
Madison Keys (USA x21) bt Tatjana Malek (GER) 6-4, 6-4
Agnieszka Radwanska (POL x13) bt Casey Dellacqua (AUS) 6-1, 6-4
Jelena Jankovic (SRB x28) bt Petra Kvitova (CZE x2) 3-6, 7-5, 6-4