Grant Hackett led the 800m qualifying while ex-Canadian Kurtis MacGillivary slammed swimming officials from the host nation after missing the final at the world titles in Montreal.

Defending champion Hackett posted a time of seven minutes 47.62 seconds to edge out American rival Larsen Jensen (7:48.89) in their heat at Parc Jean-Drapeau pool.

Russian Yuri Prilukov (7.51.75) and Welshman David Davies (7:51.92) were third and fourth quickest respectively.

MacGillivary's return to Canada has started on a sour note by being more than 10 seconds off his best time, touching the wall in 8:09.01 to be 26th in qualifying.

However the Gold Coast-based swimmer who trains alongside Hackett, remained defiant that he had made the right decision to swap nationalities at the beginning of the year.

"This is a different experience in a totally different country but I have had a lot of form in the Australian team and it is a good to be there," he said.

"I know I proved my point at trials by swimming faster than I ever have and making the Australian team which is the best team in the world."

The 21-year-old missed out on selection for the Athens Games despite recording a qualifying time at the Australian titles and a top ten world ranking.

However the final straw came when he was told he'd lose his funding unless he returned to Canada, having moved to Australia in 2001 to improve his swimming.

He was disillusioned with the Canadian system and again questioned whether it was heading in the right direction.

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