IAN Thorpe faces a mammoth battle to make the Australian swim team before he even considers gold at London Olympics, says former Australian coach Laurie Lawrence.
The comeback of Thorpe and other former elite Australian swimmers Libby Trickett, Geoff Huegill and Michael Klim has made a spot on the Australian swim team hot property, Lawrence said.
"They have been elite swimmers of the past (and) they're on the comeback trail.
"They're coming into the paddock with the young bulls. Let's see how they go."
Lawrence described the clash of old and emerging champions as "the most exciting thing that's happened in Australian swimming for a long, long time".
Thorpe, 29, announced his return to the pool earlier this year, joining a swag of former Aussie greats training for next year's London Olympic team.
Sprint sensation Trickett, 26, butterfly champion Huegill, 32, and veteran star Klim, 34, have all recently come out of retirement.
Thorpe managed the 11th quickest time in yesterday's 100m butterfly heat at the Singapore FINA World Cup, his first international competition in five years.
On Friday he finished seventh in the 100m individual medley.
"I think it's very exciting, although when you look at Thorpey's swim (on Friday night) ... I think it's a start and you've got to start somewhere, but he hasn't got a lot of time," Lawrence said.
"I think he's got an elephant to eat. But you eat it one mouthful at a time (and) I think he's eaten the leg so far."
The return of former champions made the young stars determined to perform, he said.
Lawrence said there was a troupe of young Australian swimming stars on the rise.
"There's always a changing of the guard but we really won't know if they've got enough time until London," he said.
The Australian team trials in the next few months would be the key, he said.
"It's cut throat," Lawrence said.
"If you don't go first or second at the Olympic trials, you're going to get your throat cut."
COMEBACK KINGS AND QUEENS
Ian Thorpe, 29, retired in 2006 and returned to professional swimming in 2011
Libby Trickett, 26, retired in December 2009 before announcing her return to the sport in September 2010
Geoff Huegill, 32, quit the sport after the 2004 Athens Olympics, returning in 2008 after losing more than 40kg
Michael Klim, 34, announced this year he would compete for a spot on the 2012 Olympic team after retiring in 2007