Ronnie O'Sullivan has withdrawn from the Australian Goldfields Open, the first ever ranking tournament to be held in the country.
O'Sullivan, 35, pulled out citing neck and back injuries suffered on the first leg of his journey to Australia.
The three-time world champion was due to face Dominic Dale in the last 32 in Bendigo, Victoria state.
Dale will instead play Australia's Steve Mifsud, a wild-card entry.
Mifsud's original opponent, Matthew Selt, goes straight into the last 32 to play world champion John Higgins.
The tournament starts on Monday and runs until 24 July.
A statement from World Snooker said: "Ronnie O'Sullivan has withdrawn from snooker's Australian Goldfields Open for medical reasons.
"He completed the first part of the journey Down Under, to Bangkok, but having suffered from neck and back problems on the plane he has decided to return to the UK for medical treatment rather than taking the flight to Melbourne."
In May, World Snooker chairman Barry Hearn announced a three-year deal for the Australian Goldfields Open as part of attempts to expand snooker's global reach.
"Snooker is going global like never before," said Hearn at the time.
To date, 2011 has not been a vintage year for O'Sullivan, who is ninth in the world rankings.
In March, he hinted at retirement after a poor run of form continued with a 5-2 defeat by Ryan Day in round one of the China Open.
That was his fourth successive loss in tournament opening matches and he admitted he was not optimistic about turning his form around.
O'Sullivan subsequently attempted to pull out of the World Championships, only to change his mind.
He then made it to the quarter-finals at the Crucible before losing to John Higgins, the eventual world champion.