Serena Williams has won the Australian Open in the past despite being well short of peak fitness, but the years appeared to catch up with her yesterday.
Despite carrying an ankle injury, Williams had still been one of the favourites to win here, but the 30-year-old American was knocked out by Ekaterina Makarova, the world No 56.
With Williams making 37 unforced errors and serving seven double faults, Makarova coasted to a 6-2 6-3 victory to reach the last eight of a Grand Slam event for the first time.
She now plays a fellow Russian Maria Sharapova, who beat Germany's Sabine Lisicki 3-6 6-2 6-3.
Williams, who needed painkillers and had her ankle strapped after suffering the injury in Brisbane a fortnight ago, served poorly and never got her groundstrokes going.
The world No 12 said there was "no way" she would have tried to play if it had not been a Grand Slam event.
Chris Evert described Williams' performance as shocking and added: "I have never seen her play so poorly in a Grand Slam match -- or any match.
"She was totally out of sorts. There was no rhythm. When she missed, it was by feet and not inches. She was hitting balls six, eight feet out of court. That is not the champion Serena Williams we have seen.
"At the end of the match she was just trying to push the ball back in court and she wasn't even able to do that. Maybe now she is 30 she is having more bad days, more flat days."
Caroline Wozniacki, the world No 1, is due to play Kim Clijsters, the defending champion, in the quarter-finals today and will no doubt be hoping to let her tennis do the talking after Martina Navratilova said that the Dane was not a "true world No 1".
Navratilova, who believes that Petra Kvitova would top the rankings under a fairer system, said: "Wozniacki doesn't even have that great a record in her career or in the last four years over the top 10 or against the top five, whereas Petra, you feel, really imposes herself on the match and any player." (© Independent News Service)