'One of the worst sets of tennis I've seen from him'
Roger Federer was in cruise control against Stan Wawrinka and had one foot in the final until a horrible set that left commentators stunned.
After taking the first two sets in Thursday night's semi-final showdown, Federer looked a completely different player as he dropped the third 6-1.
FED EXPRESS ROLLS ON: Federer marches into another Aus Open final
He struggled to hold serve and horribly shanked a number of regulation shots.
"I've watched a lot of Federer but I think that's one of the worst sets of tennis I've seen from him," said Todd Woodbridge in commentary.
Aussie legend Lleyton Hewitt was similarly shocked.
"One of the strangest things I've seen in any of his matches from the past 20-odd years," Hewitt said in commentary.
"My only thought is he started to get ahead of himself and started thinking he could possibly be in the final."
After dropping the fourth set as well, Federer managed to regroup and march into another Australian Open final.
Federer said he couldn't find his rhythm.
"He relaxed really, and I couldn't serve well as I did the next thing I know it was hard to stop the bleeding," Federer said.
"I fought in the fourth, and I could not get my rhythm back.
"Stan was playing with nothing to lose."
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