Here, Press Association Sport looks at some of the groundbreaking commercial contracts which have been signed by sportsmen.
TIGER WOODS (golf)
McIlroy may have overtaken Woods as the game's current best golfer, but the American's commercial income is still vast. In 2000 Woods signed a new five-year deal with Nike believed to be worth £62million. Forbes estimated he made £44million in the 12 months between June 2002 and 2003 and, with his contract being linked to sales, they claim last year he earned £34million more in endorsement income than the top 10 golfers averaged over the past 12 months.
DAVID BECKHAM (football)
The former England captain is an internationally-recognised figure and his contract with adidas reflects that. In 2003 he signed what Forbes described as the biggest commercial contract in sports history which - with a 50 per cent payment up front, a percentage of profits from sportswear sales and promotional work - amounted to £100million.
LEBRON JAMES (basketball)
Before he had even played a single minute in the NBA, James secured the biggest basketball shoe deal ever in 2003 - a reported £56million seven-year contract with Nike. He signed a new deal in 2010 on similar terms.
GEORGE FOREMAN (boxing)
Foreman made a comfortable living in the ring in the 1970s but his income stream soared when he went into retirement. In 1999 the former heavyweight champion signed a deal with Salton to put his name to their grilling machine for a reported £85million. Prior to this deal the company was paying Foreman and his two partners 60 per cent of the profits from grill sales.
HENRY COOPER (boxing)
England's heavyweight champion, whose career peaked in the decade before Foreman, did not fare so well on the commercial side as his American counterpart. Cooper was the star of Brut aftershave commercials in the 1970s and although no details of his income from that are available, when he died in 2011 he left an estate worth £747,098.
Mcilroy to join sport's richest
Rory McIlroy is all set to become one of the biggest earners in sporting history after confirmation today of a multi-year sponsorship deal with Nike.
Here, Press Association Sport lists the world's highest-paid athletes in 2012, according to Forbes business magazine.
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