With rain forcing many of Tuesday's matches to be postponed, Wednesday shaped up to be an exciting day at the 2012 U.S. Open — and it did not disappoint.

The big upset of the day was No. 1 Roger Federer falling to No. 6 Tomas Berdych. Berdych knocked out the top-seeded Federer with a 7-6, 6-4, 3-6, 6-3 victory. The other big story on the men's side was Andy Roddick's loss to No. 7 Jaun Martin del Potro. Roddick, playing in the final tournament of his career, won the opening set 7-6 before dropping the next three.

It was a busy day on the men's side, with No. 2 seed Novak Djokovic, No. 3 seed Andy Murray and No. 8 seed Janko Tipsarevic all advancing. Djokovic and Tipsarevic moved on to the quarterfinals while Murray's win pushed him through to the semifinals.

On the women's side, No. 4 Serena Williams continued her strong play with a 6-1, 6-3 victory against No. 12 Ana Ivanovic. Williams hasn't dropped a set during her five U.S. Open matches and now moves on to the semifinal. No. 3 Maria Sharapova and No. 10 Sara Errani also advanced to the semifinals with wins on Wednesday.

For a complete schedule and scores, head to the U.S. Open's schedule page.

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