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By Ian Ransom
MELBOURNE, Jan 20 (Reuters) - Agnieszka Radwanska continued her perfect start to the year with a clinical demolition of Ana Ivanovic to set up a rematch with Li Na in the quarter-finals after beating the Chinese in Sydney 10 days ago.
Four of the top 10 women have already packed their bags at Melbourne Park while fourth seed Radwanska has not dropped a set in her 13 straight victories this year.
"Well, what can I say? I'm just very happy that I can play at a very high level," she told reporters after her 70-minute rout of the former world number one. "I hope I can keep going three more."
The 23-year-old Pole joked before the match that she was not superstitious about the number 13 and needed precious little luck in her 6-2 6-4 rout of the former world number one.
Radwanska made just four unforced errors to the wayward Serbian's 34 and saved five break points in the second set before sealing victory with her seventh ace after 70 minutes.
Radwanska, who stormed to victory in Auckland and Sydney in the leadup to the tournament, has set her heart on becoming Poland's first grand slam winner and came within a set of her fulfilling her dream at Wimbledon against Serena Williams.
Her frenetic all-court game on a cool summer evening at Rod Laver Arena left Ivanovic in little doubt the Pole could go all the way at Melbourne Park.
"I think she definitely can," the former French Open champion told reporters.
"She's a player, it's no secret, who doesn't make too many winners, but she has good hands. She can really get the opponents to feel a little awkward make you go for too much.
"That's her strength."
Radwanska edged sixth seed Li in two tight sets at the Sydney semi-final but the 2011 finalist is brimful of confidence after easing past her fourth-round opponent Julia Goerges in straight sets.
"It's never easy playing against her. She's a very consistent player and moving very well, serving well," said Radwanska. "For sure I really have to play my 100 percent to beat her." (Editing by John Mehaffey)