Andy Roddick certainly should not be too tired should he face Roger Federer in the US Open quarter-finals.
Roddick, seeded five, reached the last eight at the year's final major on Monday when number nine seed Tomas Berdych retired due to illness at Flushing Meadows' Arthur Ashe Stadium.
Roddick, who won this event four years ago and was the runner-up to Federer here last year, held a 7-6 (8-6), 2-0 lead when Berdych quit the contest because of a stomach ailment.
The American explained: 'You don't want to advance because someone isn't feeling well.'
It was the second time in four rounds that the American had not had to win three sets to advance, having held a 4-6 6-1 6-2 lead when Argentinian Jose Acasuso pulled out in the second round because of injury.
In a first set which featured two breaks of serve by each player, Berdych earned a set point by smacking a forehand winner in the 11th point of the tie-break.
But the 21-year-old Czech followed by sending a forehand into the net, a backhand long and a forehand into the net from the service box to lose the set.
Two games later, he pulled out.
‘I don't know exactly what was wrong,’ Berdych said afterwards. ‘I'm not feeling really well.
‘I have just been in the doctor's. I'm going to go back there again just to take blood test and get some results.
‘I was feeling really bad, since the start of the match. I was just trying and hoping (that) maybe it's going to change or something. But I didn't feel well.’
Roddick has won just one of 14 clashes with the top-seeded Federer during his career.
The Swiss would move within three victories of a fourth straight US Open crown with a win tonight over Spain's Feliciano Lopez, and he has won all four previous matches against the lefthander.
Hoping to join Roddick in the quarter-finals is his Davis Cup teammate James Blake, the sixth seed, who is playing 10th-seeded German Tommy Haas.
The winner of that match will face either fourth-seeded Russian Nikolay Davydenko or South Korean Hyung-Taik Lee in the round of eight.
