A listless Serena Williams [Images] stumbled out of the Australian Open on Tuesday, the champion jettisoned by Serbia's "wounded animal" Jelena Jankovic.

Rafael Nadal [Images] continued his assault on the first Grand Slam of the season with a muscular defeat of Finn Jarkko Nieminen and will next meet either Jo-Wilfried Tsonga or Mikhail Youzhny who clash later on day nine.

Maria Sharapova [Images] and Justine Henin [Images] open the night session with a blockbuster quarter-final to decide Jankovic's semi-final opponent.

• Melbourne Snapshots | Images from Day 8

Listless and frustrated, three-times winner Serena was out-fought and out-thought on Rod Laver Arena, beaten 6-3, 6-4 to leave her title defence in tatters.

For Jankovic, who is recovering from surgery and plagued by niggly injuries, the 99-minute victory was sweet revenge for last year's fourth-round defeat here.

"I'm like a wounded animal, I still keep going," the third seed smiled, referring to her injuries. "The most important thing is that I fight on the court, and I always give my best and I never give up.

"Those are the qualities that got me through to the semi-final."

FEARSOME FIGHTER

Serena is known to be one of the most fearsome fighters in sport, but under clear blue skies she was impotent. Her shots lacked punch, her serve lacked bite and her tactics unravelled.

Spanish powerhouse Nadal simply wore down Finn Jarkko Nieminen for his 7-5, 6-3, 6-1 victory and a place in the semi-finals of the Australian Open for the first time.

• I'm like a wounded animal: Jankovic

The three-times French Open champion saved two set points before winning the first set and then gradually turned the screw.

"It's the third match that I have had set points against me in the first set so I'm very happy about [coming through] that," Nadal said in a courtside interview.

Nieminen was less happy.

"Against anyone it is hard to come back, but against him, you have to hit so many balls, so it would have been very important to have won the first set."

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