Graf and Agassi's latest venture

Former tennis champions Andre Agassi and Steffi Graf are to invest in and advise Europe's leading secondary ticketing company Viagogo to help it expand, the group said on Wednesday.

Viagogo, a London-based Web site which allows people to buy and sell live event tickets, said the investment from Germany's Graf and Agassi of the United States formed part of the latest round of funding which raised $15 million.

The two former world number ones have invested a seven figure sum, the company said, without giving further details.

They will sit on the advisory board of Viagogo, which has ticketing deals with soccer clubs Manchester United, Chelsea and Bayern Munich, and music companies Warner Music International, Live Nation and the artist Madonna.

Viagogo was launched in August 2006 by Eric Baker and has since grown rapidly, signings deals with sports, music and theatre groups to provide an alternative to fans who are still looking for tickets and want a reliable source.

Unlike the rest of the music industry which has been hit by piracy, the live music business has flourished in recent years, and sports clubs have also been keen to sign secondary ticket deals to keep seats filled.

Baker said Graf and Agassi would help the company in terms of their contacts to build ticketing partnerships in tennis, and in one of the site's biggest markets, Germany.

Baker previously helped start the largest secondary ticketing company in the United States, StubHub, which was sold to eBay <EBAY.O> in 2007 for $307 million.

Viagogo, which takes a commission for managing payment and delivery of tickets, has now secured a total of $70 million of external investment.

Baker said they had started looking for investment in September of 2008, at the height of the financial turmoil, and managed to close the funding round surprisingly quickly.

Viagogo now has annual sales close to a $100 million annually, he said, and they are looking to push into more European markets such as Spain and Italy, and the U.S.

He said the company was currently focussed on growing the business but it could have opportunities to float in the future. He expects people to continue going to gigs and sports events despite the downturn, but said the price of tickets could fall.