AFP

New York, Sep 2: Poland's Agnieszka Radwanska spearheaded a teenage charge at the US Open on Saturday, dethroning defending champion Maria Sharapova in a stunning third-round upset.   

The 18-year-old felled the Russian glamour girl 6-4, 1-6, 6-2 in a wind-affected morning encounter.    She was joined in the last 16 in the bottom half of the draw by two other 18 year-olds - Agnes Szavay of Hungary and Victoria Azarenko of Belarus - as well as 16-year-old Austrian prodigy Tamira Pascek.   

Sharapova had been a red-hot favourite to coast into the last 16, playing in the first match up on the Arthur Ashe Stadium centre-court.   

The second seed had won her opening two games, both played at night, for the loss of just two games and had spent just 101 minutes on court. Things worked out very differently against Radwanska.   

The Pole was not alone in the upset stakes as Szavay ousted seventh-seeded Russian Nadia Petrova 6-4, 6-4.   

She will next play Julia Vakulenko of Ukraine, a relative veteran at 24 who battled past another Russian, Maria Kirilenko, 6-2, 6-4.   

Radwanska admitted indulging in a bit of gamesmanship in trying to unnerve Sharapova by jumping about when she was serving.   

"I think she made many mistakes and double-faults so I think she was a little bit nervous," she explained. "I knew that she doesn't like it if somenody is moving when she is serving."