The world tennis number five Andy Roddick has been knocked out of the US Open by fellow American John Isner, losing 7-6 6-3 3-6 5-7 7-6 in a dramatic fifth set tiebreak.
The big-serving 2.06-metre Isner boomed in 38 aces and took the fifth set tiebreak 7-5 in posting a victory over the 2003 winner and this year's Wimbledon runner-up.
Roddick, who served 20 aces himself, says Isner's height proved too much to handle.
The 55th-ranked Isner next faces the 10th-seeded Spaniard Fernando Verdasco.
