Maria Sharapova produced a stunning performance to overwhelm world number one Justine Henin 6-4 6-0 in the Australian Open quarter-finals on Tuesday.

The Russian fifth seed smashed 30 winners as she edged a tight first set but blew away the top seeded Belgian in the second to set up a semi-final against Jelena Jankovic, who defeated defending champion Serena Williams 6-3, 6-4.

Sharapova, losing finalist in Melbourne last year, had lost six of her previous eight meetings with Henin but came out firing on all cylinders and stormed into a 5-2 lead.

Henin saved two set points as Sharapova was broken when serving for the set but the Russian broke again to win it and left the Belgian flailing in the second to reach the last four for the fourth successive year.

It was Henin's first defeat since last year's Wimbledon, ending a winning streak of 32 matches, and the first time she has lost a set 6-0 since 2002.

"I really felt like I was in my own bubble today," Sharapova said. "I came on the court, I wasn't trying to pay attention to her record or how many tournaments she won, which is an increbible number.

"It's amazing when you go out on court and you feel like you're doing the right thing."

Jankovic, the number three seed, said she fought "like a wounded animal" to overcome Williams, the Amercian eight-time grand slam champion, in straight sets in a one hour 38 minute clash where both women had to play through the pain barrier.

With Williams suffering with a huge blister, Jankovic's thigh was also proving troublesome and both players needed lengthy treatment in the second set

The Serb said she was thrilled to avenge her loss to Williams at last year's event, labelling the win her best grand slam performance as she finally overcame the injuries and poor form that marred her early matches this year.

"Getting revenge it feels so good. I'm so happy to be in the semi-final, after having no expectations, having injuries and not really thinking that I can go far," she said.

Williams, seeded seventh, was the hot favourite going into the match. She had crushed her previous opponents while an out-of-sorts Jankovic was nursing a bad back, knee and shoulder, not to mention the baggage of some hard-fought victories earlier in the tournament.

But the American shot herself in the foot with a mistake-ridden display that included 36 unforced errors, more than double Jankovic's total of 17.

The Serb began tentatively, surrendering a service break in the second game. But that was the only time the titleholder was ahead as Jankovic found her range and stunned her opponent by taking the next four games.

Williams held serve with an ace to make it 5-3 but Jankovic continued to run her around and broke again to take the first set after 36 minutes.

The pair exchanged two service breaks early in the second set, with Williams screaming in anger and smashing her racquet after conceding the second break to put Jankovic up 3-2.

Both players received courtside medical treatment after the fifth game, Williams suffering blisters on her right foot while Jankovic had a sharp pain in her left thigh.

"It was like a knife went in my leg, it was really painful," she said. "Knowing that I'm injured they think that I cannot play, but I'm like a wounded animal, I still keep going."

She and Williams ignored the pain to play on, a committed Jankovic risking further injury when she almost performed the splits sliding to produce a spectacular forehand return and go up 4-3.

She had the chance to serve for the match at 5-3 but Williams held on. Jankovic, though, made no mistake two games later.

"It was an unbelievable match and I'm still shaking," Jankovic said. "I'm so happy to be in the semi-final for the first time here in Australia. I came here with no expectations and to beat the defending champion and in general a champion like Serena, it doesn't happen every day."