Nick Bollettieri

Nicholas James Bollettieri (born July 31, 1931), is an American  tennis coach. He has participated in the development of many leading players, including Andre Agassi, Jim Courier, Monica Seles, and Mary Pierce. He also has worked with Maria Sharapova, Daniela Hantuchová, Jelena Jankovic, Nicole Vaidišová, Sabine Lisicki, Sara Errani, Tommy Haas, Max Mirnyi, Xavier Malisse, Venus Williams, Serena Williams, Martina Hingis, Anna Kournikova, Marcelo Ríos, Kei Nishikori, and coached Boris Becker for two years.