Wuhan - Agnieszka Radwanska warned on Wednesday the world's top female players are exhausted after a long season and said it was little surprise most of the seeds have tumbled out at the Wuhan Open.
Radwanska, the ninth seed, crashed out of the hot and sticky tournament at the hands of Australia's Ashleigh Barty after struggling to overcome a virus that had forced her out of the Pan Pacific Open in Tokyo.
She joined the exodus of tournament favourites including Romanian Simona Halep, seeded two, and Dane Caroline Wozniacki, the fourth seed, during the early rounds at Wuhan.
"Some of the girls are tired. Obviously it's the end of the season," 28-year-old Radwanska told AFP on Wednesday after going down 4-6, 6-0, 6-4.
"Nobody's a machine here, you can just be exhausted after a couple of months playing tennis. These things happen," the Pole said.
Wuhan falls at a busy time of year in the women's schedule, sandwiched between the Pan Pacific Open in Tokyo and the Beijing Open. They have weeks still to play before the final tournament of the season, the Fed Cup, in early November.
Caroline Wozniacki, world number six, was on Tuesday upset 7-5,6-3 in the second round by Maria Sakkari, ranked 80 in the world, just days after jetting in from Tokyo, where she captured her first title of the year. She had previously fought her way through six finals, losing in each one.
Speaking before her first match at Wuhan, Wozniacki said she found the tight schedule mentally challenging.
"I'm feeling OK (physically). It's more mentally... getting yourself up in the morning and having to be competitive and not just being able to take a chilled day," she said.
Meanwhile Halep, ranked two in the world, appeared to have the opposite problem after playing her first match since crashing out of the US Open second round a month ago.
"Maybe it was a mistake that I didn't play, but I needed rest after the US season," she told journalists after suffering a shock 6-2, 6-1 defeat to Russia's Daria Kasatkina.
"It's tough to come back and to play matches."
The three stars followed fellow seeds Johanna Konta, Sloane Stephens, Madison Keys and Petra Kvitova among others out the exit. Only four seeds remained by Wednesday evening, with one yet to finish her third-round match.
Fabrice Chouquet, co-tournament director at Wuhan, said: "It's the end of the season, probably where certain players tend to be tired, but we've always had great winners. Petra (Kvitova) twice, Venus (Williams) once, and that's just the nature of tennis."