Federer rolls Swiss to reach semis

Defending champion Roger Federer demolished fellow Swiss Stanislas Wawrinka to reach his eighth straight Australian Open semi-final Tuesday, as Li Na ratcheted up hopes of a Chinese Grand Slam win.

Federer, who can become only the second man to win five Australian Opens after Roy Emerson (six), showed no mercy against close friend Wawrinka as he took him apart 6-1, 6-3, 6-3 in just 1hr 47 min on Rod Laver Arena.

"I definitely needed a good performance and I've obviously played Stan many times in practice and in matches, and there were no real secrets out there for either of us," Federer said.

Federer and Wawrinka are known for a joyous celebration after their doubles gold at the 2008 Beijing Olympics, but the pair were poles apart as the 16-time Grand Slam winner coolly dispatched his frustrated friend.

Wawrinka, who had not been beaten this year and whipped Andy Roddick in the quarters, angrily smashed his racquet when he was broken for the fifth time, in the third set, as Federer cantered to victory.

Federer, 29, can equal Andre Agassi's record 46 hard-court titles and derail top seed Rafael Nadal's "Rafa Slam", a non-calendar year Grand Slam which would unite all four major trophies for the first time since 1969.

Meanwhile Li lifted Chinese hopes to fever pitch as she weathered an early storm from Germany's Andrea Petkovic to reach her second straight semi-final at Melbourne Park.

A day after compatriot Peng Shuai fell by the wayside, Li survived a blistering start by Petkovic in both sets to wrap it up in 80 minutes.

Li said she had no intention of repeating last year's disappointment, when she was bundled out of the last four by eventual winner Serena Williams, who is out this year with a foot injury.

"I played really well in Sydney and I hope I can do better here this year. I don't want to lose in the semis again," said Li.

Li, who is unbeaten in 2011 after winning this month's Sydney International, will play either world number one Caroline Wozniacki or French Open champion Francesca Schiavone in Thursday's semi-finals.

A maiden Grand Slam singles title would be considered a huge boost to tennis in China, where the sport has been growing exponentially after it hosted a series of top tournaments and produced its first competitive players.