The 2012 U.S. Open continued Monday, and No. 4 seed Serena Williams was among the players who advanced to the fifth round.

Williams advanced with a 6-0, 6-0 win over Andrea Hlavackova. With the straight-set win, Williams has not dropped a set in any of her four U.S. Open matches. Williams has also not dropped a game in any of her last three sets. No. 2 seed Agnieszka Radwanska did not advance, losing 6-1, 6-4 to No. 20 seed Roberta Vinci. No. 6 Angelique Kerber also lost, falling to No. 10 seed Sara Errani.

On the men's side, No. 1 seed Roger Federer advanced when Edina native Mardy Fish pulled out due to health reasons. In addition to Federer, No. 6 seed Tomas Berdych and No. 12 seed Marin Cilic also advanced to the fifth round.

Monday's complete schedule can be found at the official U.S. Open site, and live men's and women's scoreboards are available from Sports Illustrated.

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