Phelps to earn $100 mn from endorsement: Agent

Los Angeles: Olympic medal record-holder Michael Phelps could earn $100 million through endorsement and sponsorship deals, his agent told the Wall Street Journal in an interview published on Monday.

Phelps, who won a historic eighth gold medal Sunday, currently earns an estimated $3 million to $5 million - a huge amount for an athlete in a niche sport that's only shown on mainstream US television during the Olympics.

As Phelps started accumulating gold medals at the current games, his agent Peter Carlisle began receiving a growing torrent of offers for business opportunities - with more than 50 business proposals a day coming in over the weekend.

"What is the value of eight golds in Beijing before a prime-time audience in the US?" asked Carlisle. "I'd say $100 million over the course of his lifetime."

Phelps, 23, already has contracts with swimwear firm Speedo, Hilton Hotels and watchmaker Omega.

But the paper quoted sports marketing experts as saying that Phelp's new-found superstardom could yield far larger deals. Nike could pay him $40 million to $50 million if he opted to end his current relationship with Speedo in favour of the sports giant, which could use Phelps to launch its own swimming line.

But Speedo is likely to wage a tough fight to keep its star seller. The company had sold out of its entire line of tens of thousands of $25 Phelps jerseys, even though swimmers don't wear jerseys in their sport.

The company has also reported strong demand for the specialized $550 racing suits worn by Phelps and plans to launch several new versions over the coming months the paper reported.