FOUR-TIME Olympian Anthony Edwards will be the first Ballarat athlete in action when World Rowing Championships action starts tomorrow.The 37-year-old is set to line up in the Australian lightweight men's four at Lake Karaprio on New Zealand's North Island.Fellow Ballarat Olympians Sarah Heard and James Marburg will start competition on Tuesday.All 15 Australian crew members tested the course, outside Cambridge, yesterday morning to fine-tune preparations.Australia is among 49 nations at the championships, building towards the Olympic qualification year in 2011.These titles will be Edwards' 10th world championships. He last claimed a medal in 1999, with silver in the lightweight four.The Olympic triple medallist and former Ballarat Grammar rowing director started in the St Patrick's College ranks and is now Tasmania's state rowing development officer.Heard will row in the women's coxless four at her fourth world championships.She was a gold medallist with the women's eight in 2005 and claimed bronze in the same event a year later.Marburg, an Olympic and world championship men's four silver medallist, has made the switch to the men's eight this season.He joins the eight with his Olympic crewmates Francis Hegerty, Cameron McKenzie-McHarg and Matt Ryan.Ballarat's Chris O'Brien, who led Duncan Free and Drew Ginn to Olympic gold two years ago, will coach the men's four, eight and coxed pair in New Zealand.