The reigning Ironman world champion turned around to face cheering fans on either side of the tape, paused, and took a bow.

So comfortable was his lead that he did not have to stretch himself as he claimed the Aviva Ironman 70.3 Singapore men's elite title in 3hr 47min 24sec at East Coast Park on Sunday.

Fellow Australian and 2007 Ironman world champion Chris McCormack finished 3min 18sec later for second place.

Having completed the 1.9km swim and the 90.1km cycle, the duo headed into the 21.1km run almost abreast of each other.

But once Alexander found his rhythm in the run, it was his title to lose.

'I didn't feel a need to push it too hard. But it was a hard day nevertheless - given these conditions and this sort of field,' he said. 'I had a good all-round race.'

Indeed, the 22-strong pro field was star-studded, and included defending champion Simon Thompson and 2007 champion Reinaldo Colucci.

The newly crowned champion said: 'The terrain is secondary, it's the competition that makes it tough.'

But neither rivals nor jellyfish managed to stop him.

Read the full story in today's edition of The Straits Times.