Check out who won the 'battle of the undies'

Former tennis World No 1 Caroline Wozniacki was dropped from an underwear deal after the male counterpart for the brand, Cristiano Ronaldo, became too successful, it has been revealed.

Wozniacki had launched her own underwear collection in partnership with Danish company in 2012, a promotion that was heralded for its tasteful yet titillating advertising campaign.

But when Real Madrid's football sensation Cristiano Ronaldo's underwear made a similar approach, it became so big that the company decided to stop working with the tennis star, Stuff.co.nz reported.

Ronaldo launched the CR7 underwear range in 2013 in partnership with New York fashion designer Richard Chai and JBS Textile Group. The footballer had first opened a fashion boutique under the name CR7, which denotes his initials and jersey number in Madeira, in 2006. Two years later opened his second branch in Lisbon.

The impact of Ronaldo's CR7 has been far greater than they ever dream of and they thought it was best for the company to stop working with Wozniacki.