Robredo upsets Federer to reach U.S. Open quarters

Tommy Robredo stunned the great Roger Federer in straight sets Monday in fourth-round action at the U.S. Open.

Robredo, who came in winless in 10 career meetings against the Swiss legend, pulled out a 7-6 (7-3), 6-3, 6-4 victory to reach the quarterfinals of the Open for the first time in his career.

Rain forced a slew of changes on Day 8, and the pair played on the court at Louis Armstrong rather than Arthur Ashe.

Federer, seeded seventh, had not lost before the quarterfinals in 36 consecutive Grand Slam tournaments prior to a second-round loss to Sergiy Stakhovsky at Wimbledon.

The 17-time major champion couldn't start another streak as he converted just 2-of-16 break chances as opposed to 4-of-7 success rate for the 19th-seeded Robredo.

Federer's loss denied fans a shot at him facing fellow superstar Rafael Nadal in the quarterfinals. The two had never squared off at the U.S. Open.

Nadal is currently in action against Philipp Kohlschreiber, as are Monday's other scheduled fourth-round matches.