Supermaxi Wild Oats was on track to defend its Sydney to Hobart title on Wednesday after taking an early lead in the bluewater classic.
The race favorite led the 82-strong fleet out to sea from Sydney Harbor, although forecasters say "soft" winds mean the Australian yacht is unlikely to beat its record of 18 hours, 40 minutes and 10 seconds set in 2005.
Rival supermaxis Leopard and Skandia followed Wild Oats out of the harbor, intent on chasing down the title-holder during the 628-nautical-mile race down Australia's east coast to Hobart on the island state of Tasmania.
Watched from foreshore vantage points by hundreds of thousands of Sydneysiders and escorted by hundreds of spectator craft, the fleet enjoyed calm, sunny weather as the starter's gun fired.
Light winds prevented the yachts unfurling their colorful spinnakers for the opening run out of Sydney Harbor, with the calm conditions also preventing the collisions and rule infringements that have marred previous starts in the congested waterway.
The three supermaxis, the largest yachts in the race at 30 meters (98 feet) are expected to dominate the race, with Wild Oats the bookies' favorite, followed by Britain's Leopard and fellow Australian Skandia.
Wild Oats, the 2005 and 2006 winner, is bidding to become the first yacht since 1948 to win line honors three years in a row.
Sydney yacht Zephyr was leading the race for handicap honors, followed by Skandia and US yacht Rosebud.
Source: China Daily/Agencies