Novak Djokovic claimed to be summoning "wolf energy" as he racked up a 75th career win at Wimbledon.
The top seed and defending champion beat America's Denis Kudla 6-4, 6-3, 7-6 on Court One on Friday.
Djokovic will play the 17th seed Cristian Garín in the last-16.
The Serb has won nine consecutive sets since dropping the first to Jack Draper in Monday's first round contest, and battled back from set point down in the third.
"Failure was never an option for me or anyone in my family," Djokovic said after the Kudla victory.
"We needed to find the basic needs to survive. That's strengthened my character.
"I spent a lot of time in the mountains with the wolves, this is my wolf energy. I'm not kidding, actually!"
You throw everything at him, and it just comes back with interest...@DjokerNole advances to the fourth round with a 6-4, 6-3, 7-6(7) win against Denis Kudla#Wimbledon pic.twitter.com/lTy0irlrUe
— Wimbledon (@Wimbledon) July 2, 2021
Ninth seed Diego Schwatzman became only the second member of the top ten to miss out on a last-16 spot.
The Argentine lost in four sets to Marton Fucsovics. The Hungarian plays fifth seed Andrey Rublev next.
The 23-year old Russian had never been beyond the second round prior to this year, and on Friday eased past Fabio Fognini in straight sets.
Eighth seed Roberto Bautista-Agut was a straight sets victor over Dominik Koepfer to set up a fourth round meeting with either Andy Murray or the tenth seed Denis Shapovalov.
Karen Khachanov is through to round four for the first time since 2018 after straight sets win over Stefanos Tsitispas' first round conqueror, Frances Tiafoe.
VALERIE KEATLEY | Stable Staff award winner | Friday Night Racing