Petra Kvitova admitted her desire for a third Wimbledon title had left her a bag of nerves as the Czech star suffered a stunning Wimbledon first round exit.
Kvitova was the bookmakers' favourite to lift the Venus Rosewater Dish at the All England Club after an impressive return to form this year.
But the 28-year-old was beaten 6-4, 4-6, 6-0 by unheralded Belarusian Aliaksandra Sasnovich on Tuesday.
Kvitova's early exit was especially surprising given she had won five titles in 2018, including the grass-court tournament at Birmingham last weekend, while amassing an WTA Tour-leading 38 match victories.
But eighth seed Kvitova, who won Wimbledon in 2011 and 2014, revealed her burning desire to take another Grand Slam title had been her undoing against world number 50 Sasnovich.
"I'm sad. I wanted to win very badly, maybe too much. The nerves were there again. I just tried to kind of fight with myself," she said.
"Probably I was the biggest opponent I could have. I didn't really have a clear mind. I was thinking a little bit too much.
"Of course, the hand is not moving as easily as it should be, so I'm tight. I didn't move that well either.
"I think I didn't really care that much (about winning) before. I do care now. So, yeah, probably that's why."
It was another Grand Slam setback for Kvitova, who has gone out before the quarter-finals in five of her six appearances at the majors since returning to action following the horrific stabbing that derailed her career in 2016.
The knife attack had Kvitova's home left severe lacerations to all four fingers on her playing hand.
Kvitova conceded she feels extra pressure to play her best at Wimbledon after her past success and that had contributed to her collapse when she felt the Sasnovich match slipping away.
"Probably in Wimbledon it's a little bit more than the other Grand Slams because obviously I know I can play well," she said.
"But it is how it is. Yeah, I think it's the worst one.
"I think the worst pressure is in the first rounds, second rounds, and third rounds. After that it's fine."
Despite her defeat, Kvitova was actually in a light-hearted mood when she faced the media and she said that was because she still had such happy memories of Wimbledon.
"Anyway, I think I already won the biggest match here, so that's probably why I'm smiling," she added.
Sasnovich's reward for the best result of her career is a second round clash with American Taylor Townsend.
"It was good but I can play better. Probably I deserved it today," Sasnovich said after closing out the win with consecutive aces.
"I was just warming up when the score was 5-0 in the final set. I could have played one more match!"
Petra Kvitova feels the heat in her shock Wimbledon defeat