He said that American swimming coach Mark Schubert had last year, at the height of the suit controversy, said that it was a choice between winning or getting the money.

'He is being sued by a manufacturer for having said: Do you want to win or do you want the money.

'Michael Phelps has plenty of money, so who knows what it is. I think it is just loyalty and he is just gracious for everything that Speedo has done for him. But again, like I said, free will is just a gift with a price tag.'

Cavic said that he was looking forward to the final of the 100m butterfly. 'This is what I have been working for for nine months. I am definitely very excited at the opportunity.'

The Serbian said that he expects the final to be very fast with swimmers swimming under the 50 second mark.

'The Americans know I am a player, they know I have a great deal of speed. Realistically, I expect the split to be around 23 seconds.

'My race plan for tomorrow is just going out there very fast. I spent a lot of time just convincing myself that every drop of energy, every drop of blood is going to be left in the pool.

'I cant leave the race knowing that I have not given 110 per cent and I know I will give it my all.

'Everybody knows Michael Phelps is a back-half swimmer. I am not sure how he will go in the first 50, but he does not have a great deal of speed.

'He has a way of coming home and I have to get out ahead of him and stay in the lead and I just have to do the best I can. There is no point in looking.

'Michael Phelps will be there, I know that, I will just keep my head down and give it all I have. The one thing I have learnt is that you can never underestimate a Michael Phelps.'