London - Defending champion Roger Federer eased into the Wimbledon fourth round on Friday with a 6-3, 7-5, 6-2 win over Germany's Jan-Lennard Struff.
Federer took his consecutive sets won at Wimbledon to 29 in what was his 200th career grass court match.
The eight-time champion will face French 22nd seed Adrian Mannarino on Monday for a place in the quarter-finals.
"I was happy to stay clam and finish off the job. I thought I did very well today," said the 36-year-old 20-time Slam winner.
"I created more chances in the second set and was always able to stay pretty clean on my own service games."
Stefanos Tsitsipas became the first Greek man in the Open era to make the last 16 of a Slam as the 31st seed beat Italian qualifier Thomas Fabbiano 6-2, 6-1, 6-4.
The 19-year-old will faces US ninth seed John Isner for a place in the quarter-finals.
German fourth seed Alexander Zverev made the third round, seeing off Taylor Fritz of the United States 6-4, 5-7, 6-7 (0/7), 6-1, 6-2 and faces Latvian qualifier Ernests Gulbis for a spot in the last 16.
Zverev had trailed two sets to one when his tie with Fritz was halted due to darkness on Thursday.
But the 21-year-old raced away with the last two sets in Friday's bright sunshine.
"Stopping last night was not a nice feeling to go to bed with," said Zverev who said he had vomited on Friday due to a stomach bug and came close to quitting.
Russia's Ekaterina Makarova defied second round victim Wozniacki's churlish prediction that she wouldn't progress further in the tournament by reaching the last 16.
Makarova, who made the quarter-finals four years ago, beat a weary-looking Lucie Safarova of the Czech Republic 4-6, 6-1, 6-4.
She next faces Italy's Camila Giorgi who saved a match point to beat Katerina Siniakova of the Czech Republic 3-6, 7-6 (8/6), 6-2.
South Africa's Kevin Anderson, seeded eight, swept past Germany's Philipp Kohlschreiber 6-3, 7-5, 7-5 on the back of 22 aces and 42 winners.
Anderson has reached the last 16 for the fourth time and goes on to face France's Gael Monfils.
Wimbledon results on Friday, the fifth day of the 2018 championships (x denotes seeded player):
Alexander Zverev (GER x4) bt Taylor Fritz (USA) 6-4, 5-7, 6-7 (0/7), 6-1, 6-2
Roger Federer (SUI x1) bt Jan-Lennard Struff (GER) 6-3, 7-5, 6-2
Adrian Mannarino (FRA x22) bt Daniil Medvedev (RUS) 6-4, 6-3, 4-6, 5-7, 6-3
Gael Monfils (FRA) bt Sam Querrey (USA x11) 5-7, 6-4, 6-4, 6-2
Kevin Anderson (RSA x8) bt Philipp Kohlschreiber (GER x25) 6-3, 7-5, 7-5
John Isner (USA x9) bt Radu Albot (MDA) 6-3, 6-3, 6-4
Stefanos Tsitsipas (GRE x31) bt Thomas Fabbiano (ITA) 6-2, 6-1, 6-4
Karolna Plskova (CZE x7) bt Mihaela Buzarnescu (ROM x29) 3-6, 7-6 (7/3), 6-1
Kiki Bertens (NED x20) bt Venus Williams (USA x9) 6-2, 6-7 (5/7), 8-6
Julia Goerges (GER x13) bt Barbora Zhlavov Strcov (CZE x23) 7-6 (7/3), 3-6, 10-8
Donna Vekic (CRO) bt Yanina Wickmayer (BEL) 7-6 (7/2), 6-1
Serena Williams (USA x25) bt Kristina Mladenovic (FRA) 7-5, 7-6 (7/2)
Evgeniya Rodina (RUS) bt Madison Keys (USA x10) 7-5, 5-7, 6-4
Camila Giorgi (ITA) bt Katerina Siniakov (CZE) 3-6, 7-6 (8/6), 6-2
Ekaterina Makarova (RUS) bt Lucie Safarova (CZE) 4-6, 6-4, 6-1