Maria Sharapova's struggles caught up with her as she followed Serena Williams out of the Australian Open.
The third seed had spent two minutes short of seven hours on court in her first three matches, half of it in extreme heat in the second round against Karin Knapp. All appeared well when she won the first set of her fourth-round match against Dominika Cibulkova but Sharapova needed treatment for a hip problem and faded to a 3-6 6-4 6-1 defeat.
The Russian missed the latter part of last season with a shoulder problem, and she said: "Those aches and pains are expected when you spend a long time on the court. You just have to play through it.
"This is only my second tournament back, so it was those types of things that are expected.
"I haven't been playing the best tennis of this tournament, but I found ways to get through the last two matches. I tried to do that again today, but she played extremely well.
"I have to look at the positives and see where I have come from in four or five months. I haven't played a lot of tennis in those six months.
"I certainly would have loved to play a little bit more before playing a grand slam, but this is the chance that I was given.
"I'm smart enough to be able to take it and acknowledge that I'm still pretty lucky to be in the draw and giving myself a chance to try to win it."
Cibulkova, who at 5ft 3in was giving away almost a foot in height, completed her set of grand slam quarter-finals. The Slovakian, who hammered Sharapova at the French Open in 2009, said: "This is what I'm really, really happy for, finally I made it.
"I showed that I had a great pre-season in December so it feels amazing. I went on the court and I was more than 100% sure that I really could beat her. I could beat her on the big court, in an important match, at a grand slam.
"I did it before, and I knew she knows me. I also knew that she knows it's going to be a tough match. I was prepared for it."
Cibulkova next meets Romania's Simona Halep, who reached her first grand slam quarter-final with a 6-4 2-6 6-0 win over eighth seed Jelena Jankovic.