By Svebor Kranjc

EINDHOVEN, Netherlands (Reuters) - Ian Thorpe is still young enough to give the new generation of top swimmers a run for their money when he returns to the pool, his friend and former rival Pieter van den Hoogenband said on Wednesday.

Thorpe, Australia's most successful Olympian, has announced his comeback after quitting in 2006 and the 28-year-old has set himself the target of competing at next year's London Games, where he could come up against American Michael Phelps.

"The old days are over, now it's the new generation stepping up and it's a good generation, great swimmers," triple Olympic gold medalist Van den Hoogenband told Reuters in an interview.

"Michael Phelps also wants to swim 100 and 200 freestyle and racing him or racing Brazilian guys or French guys ... I am looking forward to see Ian competing with those guys and I am very happy that I don't have to compete."

At the height of his career, Thorpe was the greatest middle distance freestyler of all time, but he said he would now target the relays and the 100 and 200 freestyle.

A London showdown with Phelps, who picked up eight gold medals at the 2008 Beijing Games, would be fascinating. The pair have raced before with Thorpe beating the American in the 200 meters freestyle final at the 2004 Athens Olympics.

Van den Hoogenband, who retired in 2008 and was one of Thorpe's biggest rivals, denied the five-times Olympic champion had made a mistake in retiring at the age of 24.

"I don't think he retired too early, because he was done with the swimming and done with everything around and back then it was, I think, a good decision in his life," said the 32-year-old Dutchman.

"But he's still young and it's still possible, I am four years older, that's another Olympic cycle and I was there in Beijing so he deserves to have another Olympics and I think London is going to be fantastic."

(Writing by Sonia Oxley; Editing by Justin Palmer)