The start time for the America's Cup twice-cancelled opener between US side Oracle and Swiss defending champion Alinghi on Friday has been pushed back by two hours due to poor sailing conditions, organisers said.

The start signal for the first best-of-three race -- 20 nautical miles upwind and 20 back -- off the coast of the Spanish port of Valencia had been set for 10 am (0900 GMT) but has been put back to 11:54 am.

Earlier on Thursday Alinghi meteorologist Jon Bilger said winds in the designated race area were expected to be between 15-20 knots with waves of 1.2 metres in height on Friday morning.

"Tomorrow is pretty much on edge, looks like too much wind. It is possible to get one off in afternoon, it depends on how quickly the waves die down. Sunday is looking good," he said.

The first race was originally set for Monday but was cancelled due to weak winds which fluctuated between just 1.5 knots to a maximum of 11 knots.

It was rescheduled for Wednesday but was also called off because race director Harold Bennett deemed the waves of over two metres too dangerous for the two entries in the race, the biggest and fastest boats to ever participate in the 159-year-old America's Cup, sailing's most prestigious trophy.

In 2003 the fourth race on New Zealands Hauraki Gulf of the 31st Americas Cup match between Alinghi and Team New Zealand was delayed six times over nine days, due to winds that were either too strong or too weak.

Alinghi became the first European winner of the America's Cup that year in what was its first attempt and then succeeded in defending it in Valencia in July 2007, when summertime breezes are stronger and more consistent.