The Dutchwoman's 6-3, 7-6(1) win means that for the first time since seedings were introduced at Wimbledon in 1927 none of the top eight in the women's draw made the quarter-finals.
Kiki Bertens ensured a record exodus of seeds at Wimbledon on Monday when she added Czech Karolina Pliskova to the list of big names to perish before the quarter-finals.
The Dutchwoman's 6-3, 7-6(1) win means that for the first time since seedings were introduced at Wimbledon in 1927 none of the top eight in the women's draw made the quarter-finals.
Bertens, the first Dutchwoman to reach the last 16 since Michaella Krajicek, sister of former men's champion Richard, did so in 2007, followed up her win over Venus Williams in the third round with a display of power and poise.
Pliskova, at seven, was the highest seed to reach the fourth round after an extraordinary first week of upsets but her hopes of further progress evaporated on a stiflingly hot Court Two.
She bridled at suggestions that she had wasted an opportunity to have a real tilt at the title.
"It's not that there is a free (run) until the final," the 26-year-old said.
"You still have to beat the players.
"I don't think the draw is open. This was a match which I maybe should have won, if I maybe play a little bit better I can win. It's not that you get something for free.
"Disappointing is that I lost, but not the draw."
The tall Czech answered an early break with one of her own but 20th seed Bertens secured a second break with a superb touch volley to move 5-3 ahead and then held with ease.
Bertens built a 4-1 lead in the second set with Pliskova appearing to lack energy at times -- occasionally making little attempt to chase balls down.
But Pliskova, who reached number one in the rankings after Wimbledon last year, found some fight and capitalised on a loose game by Bertens that allowed her to break back and level the set at 4-4.
When the set drifted to a tiebreak, Bertens quickly found another gear, firing one superb forehand winner down the line.
An ace took her to 4-0 and there was no coming back for Pliskova. At 6-1 Bertens thought she had over-cooked a forehand swing volley but after Pliskova challenged the call the Hawkeye screen showed it had clipped the baseline.
She celebrated and her watching father puffed out his cheeks in relief. Bertens will play 13th seed Julia Goerges for a place in the semi-finals after the German beat Croatia's Donna Vekic.
