Former Wimbledon finalist Agnieszka Radwanska became the third of the women's top four seeds to exit this year's Championships, losing in straight sets to Ekaterina Makarova.
The 2012 finalist, seeded four, trailed the Russian 3-6 0-5 in the last-16 tie when rain forced a suspension.
Makarova, seeded 22, broke the Polish fourth seed on the resumption to reach her fourth Grand Slam quarter-final.
Highly rated Canadian Eugenie Bouchard also reached the quarter-finals.
The 20-year-old, seeded 13, won four straight games from 5-3 down in the second set to beat France's Alize Cornet 7-6 (7-5) 7-5. Cornet had ousted Serena Williams in the third round.
Bouchard came into Wimbledon in good form having already reached the semi-finals at the Australian and French Opens this year.
"I'm proud of the way I fought out there," said Bouchard, who will next play the winner of the match between Angelique Kerber and Maria Sharapova, which was postponed on Monday because of the weather.
"I am very excited about reaching the quarter-finals. But I need to stay focused. This is what I have worked so hard for but I cannot get carried away and distracted."
Barbora Zahlavova Strycova beat 16th seed Caroline Wozniacki to claim her second big scalp of this Wimbledon, and reach her first Grand Slam quarter-final.
The Czech, ranked 43 in the world, defeated the Dane 6-2 7-5 having already seen off number two seed Li Na.
"I went into the match with massive belief and this is something I was dreaming about," she told BBC Sport. "But it is going on right now; the dream is here and it is overwhelming."
Zahlavova Strycova, who served a back-dated six month ban for testing positive for a banned stimulant last year, will face 2011 champion and compatriot Petra Kvitova, who comfortably beat China's Peng Shuai 6-3 6-2, in the last eight.
"It has been a tough six months and I didn't want to play so much for a while," Zahlavova Strycova added. "But I missed the feeling of competing and decided to go for it. I'm happy I decided to play again."
Wozniacki, who saved five match points before succumbing, said it was "one of those matches" but felt her opponent was pushing the time limits between points, something for which men's number two seed Rafael Nadal was criticised earlier in the tournament.
"I thought she was very slow, but I guess the referee, she has the time on it and if she is within the time, I guess it's OK," Wozniacki said. "It is up to the referee or up to the umpire to say if she is or not."
The Dane added: "I wouldn't mind, you know, to have a [shot] clock. It shows exactly how much time you take in between points."
The 23rd seed Lucie Safarova also progressed to the quarter-finals with a 6-0 6-2 win over fellow Czech Tereza Smitkova and will face Makarova in the last eight.
It will be the 27-year-old's first Grand Slam quarter-final since the 2007 Australian Open.
Elsewhere, American teenager Madison Keys pulled out of her third-round clash with Kazakh player Yaroslava Shvedova because of a thigh injury.
The Eastbourne winner was due to resume at 6-7 (7-9) 6-6 on Monday but the injury, which she sustained during the second set on Saturday, forced her to withdraw.
Shvedova will face last year's beaten finalist Sabine Lisicki in the fourth round after the German, seeded 19, beat former world number one Ana Ivanovic 6-4 3-6 6-1 in a match suspended on Saturday.