German fourth seed Alexander Zverev and women's world number one Simona Halep wilted in 33-degree heat and crashed out of Wimbledon in the third round on Saturday.
Zverev, playing for the third day in succession, was shocked by Latvian qualifier Ernests Gulbis, ranked 138, in a gruelling five sets, 7-6 (7/2), 4-6, 5-7, 6-3, 6-0.
Despite being widely-tipped to be a Grand Slam threat, it was another letdown for the beanpole German whose run to the quarter-finals at Roland Garros last month remains his best performance at the majors.
Gulbis, a former world number 10 who famously defeated Roger Federer on his way to the French Open semi-finals in 2014, will be playing in the last 16 at Wimbledon for the first time at the 11th attempt.
The 29-year-old will take on either Australian Nick Kyrgios or Japan's Kei Nishikori for a place in the quarter-finals.
His win on Saturday was his third successive five-setter having also played three matches in qualifying.
"It's a great day, it's been a great match for me," said Gulbis who before Wimbledon had won just one match on tour in 2018.
"I didn't think I could win after losing the third set, but he got tired and I played smarter."
French Open champion Halep was also knocked out, losing to Taiwan's Hsieh Su-Wei 3-6, 6-4, 7-5 as the seeds' carnage continued.
Defeat for Halep means that Karolina Pliskova, at number seven, is the only women's top 10 seed to reach the fourth round.
It's the first time in the Open era that none of the top five women's seeds have made the last 16 of a Slam.
It also further boosted Serena Williams's chances of becoming an eight-time Wimbledon champion.
Hsieh, the world number 48, battled back from 2-5 down in the final set and saved a match point when the Romanian served for the match at 5-3 in the decider.
It will be Hsieh's first appearance in the last 16 at Wimbledon where she will face Dominika Cibulkova of Slovakia.
"It's my first win against a world number one," said 26-year-old Hsieh.
"It's amazing. I was 2-5 down in the final set but the crowd pushed me to fight."
Halep was left to rue her lost opportunities.
- 'Unprofessional' Halep -
"I was leading the match, I was up, and I couldn't finish it," said the 2014 semi-finalist.
"It was an unprofessional attitude from me today."
Two-time champion Rafael Nadal reached the last 16 for the eighth time, making sure of keeping the world number one ranking.
The second seed comfortably defeated Australian teenager Alex De Minaur 6-1, 6-2, 6-4.
Nadal, the 11-time French Open champion and bidding for an 18th career major, will next face unseeded Jiri Vesely of the Czech Republic.
"It was a positive match against a player with a lot of energy," said Nadal, the 2008 and 2010 champion.
"I am just happy to be in the fourth round again."
Juan Martin del Potro made the last 16 for the first time in five years when the Argentine fifth seed defeated France's Beno�t Paire 6-4, 7-6 (7/4), 6-3.
The former US Open winner, who made the semi-finals in 2013, next faces unseeded Gilles Simon of France.
Later Saturday, three-time champion Novak Djokovic plays his first match this year on Centre Court against Britain's Kyle Edmund.
Djokovic, the champion in 2011, 2014 and 2015, faces the home country's last remaining singles player looking to snatch another landmark.
Victory would see him reach the last 16 of a major for the 44th time to take him second on the all-time list.
Kyrgios, fresh from a social media row with former women's champion Marion Bartoli after she accused him of squandering his talents, plays Japan's Nishikori.
Kyrgios, the Australian 15th seed, is bidding to reach the fourth round for the fourth time.
Nishikori, seeded 24, bids to make the last 16 for a third time and record his 350th career win.
Other winners on Saturday included Belgium's Alison Van Uytvanck who followed her upset of defending champion Garbine Muguruza by beating Anett Kontaveit, the 28th seeded Estonian, 6-2, 6-3.
Van Uytvanck will meet fellow last-16 debutant Russian 14th seed Daria Kasatkina, who defeated Ashleigh Barty of Australia 7-5, 6-3.
Switzerland's Belinda Bencic, a former top 10 player whose ranking slumped out of the top 300 last year after wrist surgery, made the fourth round for the second time with a 6-1, 7-6 (7/3) win over Spain's Carla Suarez Navarro.
Bencic, now at 56 in the world, next faces two-time Grand Slam champion Angelique Kerber who swept past Naomi Osaka of Japan.
Shock win: Latvia's Ernests Gulbis on his way to beating Alexander Zverev
Down and out: Alexander Zverev
Day to remmeber: Taiwan's Hsieh Su-Wei celebrates beating Simona Halep