Federer, Agassi headline U.S. Open field (AP). Two-time champions Roger Federer and Andre Agassi will headline the U.S. Open men's singles field. Agassi will make his record 21st straight U.S. Open appearance, passing Jimmy Connors' Open-era record. Agassi, who won in 1994 and 1999, announced last month that he will retire after the Aug. 28-Sept. 10 Grand Slam event in New York. [Yahoo! Sports - Tennis News]