The biggest match in Andy Murray's sporting life was being threatened by a familiar problem at Wimbledon today - the British weather.

Rain delays left the Scotsman frustrated as he waited for his potentially epic quarter-final clash with world No2 Rafael Nadal, scheduled to be the second match on Centre Court.

Even Roger Federer couldn't beat the conditions although he did his best in the half-hour of play available on Centre Court as he took the first set 6-1 off Mario Ancic in 20 minutes. The second set was tied at 1-1 when rain stopped play for just over two hours until 4.37pm.

In the other quarter-final on Court One before the rain came, Marat Safin received a code violation for ball abuse after whacking one in disgust out of the vast arena. The temperamental Russian also slammed his racquet down on the turf as he trailed Spain's Feliciano Lopez 5-2.

Forecasters warned that rain could come and go well into the early evening, raising fears that the British No1's game might not even start today.

But the No12 seed was steeling himself to be patient after both he and Nadal were forced to head for cover when the first rains came just as they were both on the practice courts.

"There could be some breaks so you just have to be patient, stay relaxed and not think too much about it," said Murray.

"This hasn't happened to me very often although I know Rafa had a bad experience with it last year. There were quite a few of his matches that were stopped. If you do get on court I think the most important thing is to try and not rush things."

The first eight days of the tournament have been blessed by exceptional weather but rain is now forecast for the rest of the week, leaving organisers with a potential headache.

But Federer, looking for a sixth straight Wimbledon title, appeared to believe he could beat the weather as he produced what Boris Becker described as "the best set of tennis in the championships".

Croatia's Ancic, the last man to beat Federer on grass 63 matches and six years ago, was expected to give the Swiss

supremo, who's not yet dropped a set at the tournament, his sternest test of the championships so far.

Yet Federer, when they finally got on to court more than 45 minutes late, made a nonsense of that prediction, losing only one point on his serve.

He crashed down seven aces and twice broke the serve of Ancic, who found himself constantly having to deal with the champion's returns around his ankles.

It was one game all game in the second set before the rain became heavier at 2.30pm and the players were forced off.