Play has been abandoned at Wimbledon without a single shot being struck.

The announcement of a wash-out came just before 1900 BST after a miserable day when persistent showers ensured the covers never came off the courts for more than a few minutes.

Officials announced that all matches on outside courts on Thursday and Friday would begin at 11am, with matches on Centre Court and Court One on both days beginning at 12 o'clock.

All men's doubles matches have also been reduced to best of three sets up until but not including the quarter-final.

Defending champion Roger Federer was one of five top 10 men's seeds to fall foul of the weather.

The top-seeded Swiss was scheduled to face Colombian Alejandro Falla in the fourth match to be played on court one.

Lleyton Hewitt, Juan Carlos Ferrero, Carlos Moya and Sebastien Grosjean must all wait until Thursday for the chance to advance to the third round.

In the women's draw the rain hit the clash between third seed Venus Williams and Croatian Karolina Sprem.

``We're not unduly concerned,'' said tournament referee Alan Mills.

``Officially, we're 45 matches behind and, if we were thinking of playing on Sunday, that would not be until Friday.

"Obviously, we would like not to play on the middle Sunday.''

The middle Sunday has been used just twice in the 118-year history of the championships.

In 1991 only 52 out of a scheduled 240 matches were completed by the end of the fourth day while in 1997 two days were completely washed out.