Mardy Fish gives Roger Federer a bye – so Andy Roddick flies US flag alone

Tomas Berdych en route to beating Nicolas Almagro yesterday (EPA)

It was not the way he would have wanted to do it but Roger Federer yesterday extended his remarkable record of consecutive appearances in Grand Slam quarter-finals to 34. The 31-year-old Swiss was given a free passage into the last eight of the US Open when Mardy Fish withdrew just hours before they were due to meet here in the fourth round.

Fish, who had minor heart surgery earlier this year, said he was pulling out on medical advice, though he did not give details. The American said last week that there were still doubts over his health. He did not give a press conference following his last match against Gilles Simon for medical reasons.

Federer's extraordinary record of consistency is reflected in the fact that only five other men – Feliciano Lopez, David Ferrer, Fernando Verdasco, Tomas Berdych and Albert Montanes – have played in the last 34 Grand Slam events. Federer is currently appearing in his 52nd consecutive Grand Slam tournament, which is nine more than Lopez, who has the next best current record. Berdych will be the world No 1's quarter-final opponent following a 7-6, 6-4, 6-1 victory over Nicolas Almagro.

Fish's withdrawal leaves Andy Roddick in a familiar position as the only American left in the men's singles. Roddick, who announced last week that he would be retiring at the end of this tournament, will meet Juan Martin del Potro in the fourth round today.