Nicholas James Bollettieri (July 31, 1931 – December 4, 2022) was an American tennis coach. He pioneered the concept of a tennis boarding school, and helped develop many leading tennis players during the past decades, including Andre Agassi, Jim Courier, Monica Seles, Venus Williams, Serena Williams, and Maria Sharapova. Bollettieri was also a tour traveling coach, the last time having been for and with Boris Becker for a span of two years. Wikipedia
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