London: Roger Federer and Novak Djokovic marched into the business end of Wimbledon as they reached the last 16, while women's top seed Angelique Kerber scraped through on Saturday.
Seven-time champion Federer made it into the fourth round for the 15th time with a 7-6 (7/3), 6-4, 6-4 win over Germany's Mischa Zverev.
The Swiss great said: "I'm very happy now to sit back, relax a day and come back strong, hopefully, on Monday", when he faces Grigor Dimitrov, who has been nicknamed "Baby Fed".
"Every time I play against him he's stronger than the time before.
"I'm ready for a tough one but sure again, another exciting match because he's a great shotmaker."
All the men's and women's fourth round matches take place on Monday.
Third seed Federer was joined by Djokovic, who fended off being a break down in the first set and taken to a tie break in the third before beating Ernests Gulbis 6-4, 6-1, 7-6 (7/2).
"I'm delighted with the performance. I thought I raised the level of tennis," said three-time champion Djokovic after making the second week without dropping a set.
The second seed next faces Adrian Mannarino, who overturned French compatriot and 15th seed Gael Monfils in a five-setter.
Kerber pushed to the brink:
Kerber looked mightily relieved after saving her world number one status in a tense 4-6, 7-6 (7/2), 6-4 win over US world number 70 Shelby Rogers.
The German star was a break down in the second set but did just enough to claw her way into Monday's fourth round where she will face Garbine Muguruza.
"It was for sure a really important win for me, especially because it was a really up-and-down match," Kerber said.
In a bizarre interlude, Sam Querrey took one game to beat Jo-Wilfried Tsonga.
Their match was suspended Friday at 6-2, 3-6, 7-6 (7/5), 1-6, 6-5 due to bad light. They came back Saturday but it was all over in minutes as the US 24th seed broke serve.
"My opponent was good today. He did three, four good shots, and yeah, that's it," said Tsonga.
Querrey said: "It's really the most anti-climactic way to finish a match."
He faces South Africa's Kevin Anderson for a quarterfinal spot.
Canadian sixth seed Milos Raonic, last year's beaten finalist, downed Spain's 25th seed Albert Ramos-Vinolas 7-6 (7/3), 6-4, 7-5 to book a fouth round spot against Alexander Zverev.
The German 10th seed beat Austrian qualifier Sebastian Ofner 6-4, 6-4, 6-2.
Dimitrov given a leg-up:
Bulgarian 13th seed Dimitrov had an easy ride when Israeli Sela was forced to pull out at 6-1, 6-1 down after struggling with a right thigh injury.
Tomas Berdych, the 2010 finalist, beat David Ferrer in straight sets.
The Czech 11th seed will play Austrian eighth seed Dominic Thiem who saw off Jared Donaldson of the United States in straight sets.
Spain's world number 15 Muguruza, the 2015 runner-up, comfortably beat Sorana Cirstea 6-2, 6-2.
The out-of-sorts Romanian had witnessed the horrific knee injury suffered Thursday by her last opponent, Bethanie Mattek-Sands.
The American wept as she relived the sickening injury which has left her facing surgery to repair a dislocated knee.
"I have had lots of injuries in my career but this is definitely the worst," she said Saturday from her hospital room in Wimbledon.
"I will be out for a while but I will get through this."
Wozniacki, Radwanska dig deep:
Wozniacki dug herself out of trouble when pushed to the brink by Anett Kontaveit, but the Danish fifth seed eventually beat the world number 38 from Estonia 3-6, 7-6 (7/3), 6-2.
She next plays 24th seed Coco Vandeweghe, considered by some as a dark horse for the title, who beat US compatriot Alison Riske 6-2, 6-4.
The deft Agnieszka Radwanska, the 2012 beaten finalist, came back from a set down to beat Swiss 19th seed Timea Bacsinszky 3-6, 6-4, 6-1 on Centre Court.
The Polish ninth seed next faces Russian eighth seed Svetlana Kuznetsova, the 2004 US and 2009 French Open champion, who cruised through with a 6-4, 6-0 win over Slovenian qualifier Polona Hercog.
Croatia's Petra Martic, ranked 135, is the last qualifier still going at Wimbledon after beating Kazakh wild card Zarina Diyas 7-6 (8/6), 6-1.
Martic next faces Slovakia's Magdalena Rybarikova, who eased into the last 16 of a major for the first time with a 6-2, 6-1 win over Lesia Tsurenko of Ukraine.
