Novak Djokovic and Roger Federer headline 'Manic Monday' at Wimbledon with the two Grand Slam heavyweights looking to edge closer to a dream title showdown.
World number one Djokovic, chasing a sixth Wimbledon title and record-equalling 20th major, is already halfway to becoming just the third man to complete a calendar Grand Slam.
The Serb faces Cristian Garin of Chile while eight-time champion Federer takes on Italy's Lorenzo Sonego.
Chilean 17th seed Cristian Garin had never previously won a main draw match at the tournament before this year. However, the 25-year-old from Santiago is in the last 16 of a major for the second consecutive Grand Slam.
"It feels amazing. I didn't play a grass tournament before Wimbledon, so I was a bit out of rhythm and without any matches on grass," said Garin who lost his only clash with Djokovic at the ATP Cup in 2002.
"My last match on this surface was here at Wimbledon in 2019."
Federer, just five weeks shy of his 40th birthday, is in the Wimbledon last 16 for the 18th time.
In all, it will be his 69th appearance in the fourth round of a Slam but he was quick to salute Djokovic's
"It's just very, very impressive to see what he's doing this year," said Federer whose third round win over Cameron Norrie gave him the 1,250th victory of his career.
Second seed Daniil Medvedev staged a stunning comeback from two sets down for the first time in his career to beat 2017 runner-up Marin Cilic and make the fourth round for the first time. Medvedev faces Polish 14th seed Hubert Hurkacz.
Sebastian Korda, whose father Petr made the quarter-finals in 1998, celebrates his 21st birthday on Monday.
He can reach the quarter-finals of a Slam for the first time by beating Russian 25th seed Karen Khachanov.