Illness and injury has ravaged the Australian Open – with Serena Williams, Svetlana Kuznetsova and Gilles Simon all advancing to the quarter-finals when their opponents quit their matches.
|Monfils was forced to throw in the towel [AFP]
Gael Monfils and Zheng Jie waved Simon and Kuznetsova through by pulling out with wrist injures while Williams advanced when Victoria Azarenka staggered off centre court in tears, off-balance and barely able to hold her racket.
Thirteenth-seeded Belarussian Azarenka had been leading 6-3 2-4 but finally quit in tears after unsteadily patrolling the baseline for several points.
Azarenka needed to be assisted off court by two trainers, supporting her either side.
"Well I just woke up this morning feeling sick already, threw up all morning," Azarenka said on Monday.
"They think it was a virus or something."
Three-times champion Williams will play Russian Kuznetsova in the quarters after Zheng retired with a wrist injury.
"I want to try to play, but I can't use the left hand, cannot play the backhand," Zheng said.
'Strongest are blessed'
"Only the strongest are blessed," said Kuznetsova, who led 4-1 in the first set when Zheng threw in the towel.
"You know, the saying? We say it in Russian.
"I felt sorry for her because she was in great shape.
"She was playing good."
Sixth seed Simon suffered a bittersweet experience, advancing to the quarters after friend and fellow Frenchman Monfils was forced to retire with a wrist injury.
Simon had been leading 6-4 2-6 6-1 and ahead 30-0 in the first game of the fourth set while serving when Monfils, who had been continuously flexing and shaking his right hand throughout the match, called a halt to proceedings.
"Well, you never want to win like this," Simon said.
"It's already strange when it's another player, but when it's a friend like Gael it's more difficult."
Simon will meet either Spanish top seed Rafael Nadal or Chilean Fernando Gonzalez.
Elena Dementieva stretched her winning streak to 14 matches when she demolished Slovakia's Dominika Cibulkova 6-2 6-2 to advance.
The Russian fourth seed now meets the dangerous unseeded Spaniard Carla Suarez Navarro, who knocked out sixth seed Venus Williams, in the quarter-finals.
"I think she's a very tough player," the Russian said.
"She plays a very unique style of game. A lot of spin. It's gonna be a tough match."
Suarez Navarro beat fellow Spaniard Anabel Medina Garrigues 6-3 6-2.
The 20-year-old, who speaks only a few words of English, is one of two unseeded women through to the last eight, along with Australian Jelena Dokic.