Rome - When Serbian 50m butterfly winner Milorad Cavic tried to rattle Michael Phelps' cage ahead of Saturday evening's 100m butterfly final, the American superstar simply said he would let his swimming do the talking.

And Phelps was loud and clear.

Lying only fourth at the first turn with 23.36, Phelps was 0.67 seconds behind Cavic, but in the end he was 0.13 seconds ahead, having won in world record time of 49.82.

Seconds after touching for his victory, Phelps exploded in a way in which he had never done so before.

He jumped on the line markings that separated him from the beaten challenger and screamed, a finger outstretched towards the sky. He then pointed towards his bodysuit, a Speedo LZR Racer.

Cavic had earlier in the week offered to buy Phelps an all- polyurethane suit, but as he pointed out after the race, he clearly did not need one.

Then he swam over the markings, ignoring Cavic and congratulated Spain's Rafael Munoz, who had taken the bronze.

In Beijing, Phelps had beaten Cavic in the final of the same event by the length of a fingernail and Cavic still maintains that he was the real winner and that the timing simply did not work correctly.

This time it was much clearer, even though Phelps thought that it would again go down to the wire.

He said before the race that he could afford to be behind Cavic at the turn, but not by more than a second. "I felt so good coming off the wall. My kick off the wall felt really, really good.

"I saw the splash out of my left eye from his lane coming over, and I saw him getting closer and closer, and I heard the crowd getting louder and louder. I figured it was going to come down to the touch again."

During the medal presentation, Phelps again showed that this must have been one of the most important victories of his career, as he was visibly eager to mount the podium.

While the stadium announcer was still calling out his name, Phelps already had one foot on the podium, as if he wanted to say: "This belongs to me." And when it was his time, he jumped up and stretched both arms out.

Although there was a terse handshake between him and Cavic and they stood together displaying their medals, it was clear that there is not much love lost between the two.

"Even before the race it was like a weigh-in for a boxing match. It was a real show-down. And then at the end, obviously, I was very excited and trying to let all my emotions go."

Phelps said he thought a rivalry such as theirs was good for the sport. "It brings a lot of excitement."

He added that he had been watching old videos. "I saw the excitement that I used to have and the emotions that were going through my head.

"Those were the good memories and I wanted to get back to that. I think this meet has brought me back to that and I think it will help me over the next years."

What made Phelps' victory even more remarkable was that his preparations had gone astray when he had a head-on collision with another swimmer during the warm-up.

His coach Bob Bowman said that in the process, his goggles had broken. "He was doing his butterfly and crashed into a girl swimming backstroke, breaking his goggles.

"He said he had blurry vision, but he managed to compete the warm- up and then he was fully examined by a doctor, who said he could go ahead and swim."

And swim he certainly did - probably as well as he has ever swum in his life.(dpa)