Radwanska dumped out of US Open by Russian Makarova

Poland's third seed Agnieszka Radwanska has been bundled out of the US Open by Russia's Ekaterina Makarova in the biggest shock of the women's event at Flushing Meadows.

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Makarova struck a barrage of groundstroke winners to topple Radwanska 6-4, 6-4 in the fourth round under floodlights on Louis Armstrong Stadium.

Radwanska started brightly, surging to a 4-0 lead, but Makarova peeled off eight straight games to take the first set and lead 2-0 in the second.

Radwanska fought her way back, holding four break points to level the second set at 4-4.

Makarova, the 24th seed, sealed the game with an ace before going on to close out the match in one hour and 32 minutes.

Radwanska's loss left her out of the quarter-finals at a major for the first time this year.

Her next opponent will be China's Li Na after the fifth seed defeated Serbia's Jelena Jankovic 6-3, 6-0 on Arthur Ashe Stadium's centre court.

The 25-year-old Russian will play her first quarter-final at the US Open after twice reaching the last eight at the Australian Open.

"It feels amazing, I really love this tournament," she said.

The fifth-seeded Chinese, who overturned last year's defeat by Laura Robson by beating the Briton in the third round, snapped a four-match losing streak to the Serbian dating back to Paris in 2009.

Former French Open champion Li cracked 20 winners and conceded only 12 unforced errors in a dazzling display, converting all her seven break points in a 57-minute master class.

"The last time in Rome I lost in two sets straight away. She plays pretty good defence, but who knows, maybe I played the best match of my whole life," Li said with a chuckle in her on-court interview.

"I still remember last time I played her in Rome. I was feeling I played pretty good, but still lost the match," she told reporters. "So I was so sad after the match."

Li said her coach Carlos Rodriguez used that defeat to motivate her.

"Before this match, Carlos didn't tell me anything. Just said, 'remember how you felt after that match.'

The victory put 31-year-old Li, Asia's first Grand Slam singles champion, into the US Open quarter-finals for the second time following her trip to the last eight in 2009.

"Tonight she played really well, at a very high level," Jankovic said of Li. "I did not control the points. I let her do all the talk on the court.

"If she continues to play like this I think she can win the tournament."