Tennis: Maria Sharapova in Aussie Open q-finals after tough win over Belinda Bencic

Maria Sharapova celebrating after her fourth round victory over Belinda Bencic. PHOTO: REUTERS

MELBOURNE (AFP) - Maria Sharapova ground her way into her eighth Australian Open quarter-final on Sunday (Jan 24), beating highly rated Swiss teenager Belinda Bencic after a titanic struggle.

The Russian five-time Grand Slam champion needed 2hr 5min to get past the 12th seed 7-5, 7-5 on Rod Laver Arena and set up a last-eight clash with arch-rival Serena Williams.

The women's world No. 1 had little trouble against Russian Margarita Gasparyan, winning 6-2, 6-1 to put her in another battle against world No. 5 Sharapova, whom she beat in last year's final.

She has won all their contests since 2004.

"These are the players that will ultimately take our spot," Sharapova said of the talented Bencic. "But not just yet. I was really focused today. It's always great to play against the players coming up for the first time."

Bencic, the WTA's highest ranked teenager, has gone from rising star to the real deal over the past year, having already claimed 10 top-10 wins in her career. Coached by Melanie Molitor, mother of Martina Hingis, she won tournaments in Eastbourne and Toronto in a breakout 2015 and was a major hurdle for the Russian.

But Sharapova - the last teen to win a Grand Slam women's singles title, aged 19 at the 2006 US Open - has been in good form at Melbourne Park, where she won in 2008, and ultimately her big-match experience proved decisive.

In the men's singles, Japanese star Kei Nishikori stormed into the quarter-finals with a convincing 6-4, 6-2, 6-4 win over former finalist Jo-Wilfried Tsonga in just over two hours on Hisense Arena.

The seventh seed will face either world No. 1 Novak Djokovic or French 14th seed Gilles Simon in the last eight.

It is Nishikori's third Australian Open quarter-final and fifth overall in Grand Slams, one fewer than the Japanese record of six held by Jiro Satoh, who died in 1934.

"I felt very good today, especially against Jo, it's great to win in straight sets and I'm very happy to play a good match today to go into the quarter-finals," Nishikori said. "I am trying to think one match at a time. I don't even know what round I'm playing and I am just trying to focus on what I have to do and try to get a good recovery for my next match."

Nishikori trails Djokovic 2-5 in their overall head-to-head, and he has never faced Simon.

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