DOHA: Karolina Pliskova on Wednesday (Feb 13) became the fifth player all from the world's top 20 to withdraw from an injury-ravaged Qatar Open.
The world number five joins Caroline Wozniacki, Ashleigh Barty and Caroline Garcia as a player who has pulled out since the tournament started, as well as newly-crowned Australian Open champion Naomi Osaka, who withdrew days before the start.
"From the first day I was not feeling great and not ready," the Czech star and former world number one told reporters.
"I have never felt actually this way. It's normal that you are tired, of course, when you are travelling and playing a lot of matches.
"But I just feel somehow my body is not ready, I had a temperature for a few days.
"I don't have any neck pain or something, but I just feel overall like super tired, and my muscles are just hurting from the morning without even doing anything.
"So I'm just not able to compete 100 per cent today."
Pliskova, the number two seed in Qatar, was due to play her first match of the tournament on Wednesday, against Belgium's Elise Mertens.
Unusually, her place in the tournament has been taken by her twin sister, Kristyna.
Karolina played in a gruelling three-hour Fed Cup tie against Romania's Simona Halep, who is also in Doha, at the weekend.
Pliskova said "it would be better" if Fed Cup matches were played on Friday and Saturday rather than over the weekend.
Asked if she thought players should think more about fans and tournament organisers before withdrawing, Pliskova said: "I don't know what else you want to do.
"If the players are sick, what can they do?
She added: "If it's not possible, it's not possible."