In 1996, Martina Hingis was at the height of her tennis-playing career and ranked number one in the world. Italian sportswear manufacturer Sergio Tacchini handed her a five-year, $5.6 million (£3.4 million) sponsorship deal to promote its products, which obliged her to wear its trainers and gear on court.

In 2001, Hingis sued Tacchini, claiming their trainers had caused her injuries and were unsuitable for tournament play. The company had already dropped her for "extremely discrediting statements concerning her main sponsor". A New York court threw out her suit, saying it had to be heard in Milan, as that was where the contract had been signed.

While that was the end of that, some damage had been done and it marked the beginning of a turbulent period for Sergio Tacchini as it lost market share to its rivals. The company was bought out by Hong Kong businessman Billy Ngok in 2008 and currently sponsors Australian Open tennis champ Novak Djokovic.

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