One of Ian Thorpe's greatest swimming rivals believes the returning Olympic champion can add to his gold medal tally next year in London.

Dutchman Pieter van den Hoogenband, who won three Olympic gold medals between 2000 and 2004, says he was delighted to hear Thorpe was coming out of his four-year retirement to make a tilt at London 2012.

And the 32-year-old thinks Thorpe can complete the freestyle sprint set and win his sixth Olympic gold.

"I think he can win the 100m freestyle," van den Hoogenband told AAP from the Laureus Sports Awards in Abu Dhabi.

"That would be something. To have the 400m, 200m, 100m Olympic gold medal is history, that's amazing.

"I'm one of the few swimmers that was always next to him and when you're always next to him ... you know he's special. When you're racing Thorpey, his technique, he's a special, special athlete."

Van den Hoogenband believes Thorpe should tackle the 100m freestyle to set up a mouthwatering showdown with American Olympic great Michael Phelps in the pool in London.

"I think Phelps also wants to win the 100m freestyle," he said.

"First I think Thorpey has to focus on the relay. He's a legend and for the Australian teammates to have Thorpey in their team, they will bring something extra.

"He can use the team, and train with the team, to do well as an individual.

"Even if he doesn't win the 100m freestyle but wins a medal with the Aussie 4x100 or 4x200 relay teams, that would be fantastic too."

While van den Hoogenband conceded he's not a fan of sporting comebacks, something he witnessed during Thorpe's press conference to confirm his decision last week in Sydney had altered his opinion on this occasion.

"I'm not a big fan of great athletes making a comeback because many times it's a big disaster," he said.

"But Thorpey is still young.

"We both know why he stopped swimming. He was done with it but when I saw his press conference I saw his eyes were twinkling and he was happy to talk about it, happy to tell the world he's making a comeback.

"There's a big chance he will be very, very successful."

Ed Jackson
AAP