Australian swimming

There are people over the age of 28 still competing at the highest level, especially in the shorter distances such at the 100m freestyle, but the fact he has been out of the sport for four years will be the biggest hurdle for him to overcome, physically and mentally.

I'm always sceptical when people come out of retirement, and I say they are only doing it for the money. But he has categorically said that his return is not for the money and it is for the challenge and to be fair to him he did leave the sport early.

It's going to be massive competition in London and gives the 2012 Olympics a very high profile with Phelps going for 20 gold medals [he has 14 already]. Thorpe is probably thinking he could be the person to stop Phelps in the blue riband event, the 100m free, and seal his place in history.

Personally I don't really rate Thorpe's chances. I know that sounds insane but there is a whole array of other swimmers who will challenge him. He has been out of the game for four years and in that time world records have been broken and the sport has moved on and the expectations of swimmers has moved on.

Nonetheless it is still a mouth-watering prospect but we've got to be fair to Thorpe and not put too much pressure on him.

It probably enhances the profile of the Games a little but it does create a lot more attention to the swimming pool. I'm selfish, I'm a swimmer and I want there to be a lot of attention on my sport and this can only help

It's great for the sport that Ian has decided to make a comeback.

He retired very young and was an absolutely incredible swimmer and he had an incredible career. You could sort of understand why he decided to retire because he achieved everything there was to achieve. But the fact he is motivated and is excited about the challenge is great for the sport

It's going to be difficult for him to be as good as he was and as dominant as he was. A lot has happened and the sport has moved on quite a bit. However, the majority of improvements in terms of times have come because of the new swimsuits which he never had the benefit of. But now we are back to the guys swimming in shorts, and it is more of a level playing field so the margins of difference might not actually be that great.

It has been a long time but he is a phenomenal athlete and so much of swimming is down to motivation. He has clearly been in the water and is obviously happy with how things are going. He wouldn't put it all on the line if he wasn't happy and if there wasn't a spark there. He is still young enough to be able train hard and put the hours in.

It's going to be interesting because the events he swims are the toughest because there is a depth of talent such as in the 200m freestyle.

It won't be as simple as just Thorpe and Phelps going head to head as there is a host of other talent but the prospect of those two swimmers in the water racing is just so exciting.

This will raise the profile of swimming at the Olympics further. The pool is the most iconic venue of the Games. Michael Phelps alone is a massive draw, especially after his performance in Beijing and him saying he wants to add another six medals at London. But now the possibility of the two greatest swimmers we have ever known being in the same race is going to be huge.

I don't think it matters that there will be other people going for that gold medal. It is just so exciting, I can't wait to be there myself