Renowned tennis coach Nick Bollettieri has died at the age of 91.

The charismatic American pioneered the concept of a live-in academy and worked with some of the biggest names in the sport, including Andre Agassi, Serena and Venus Williams, Maria Sharapova, Monica Seles and Boris Becker.

Known for his gravelly voice, leathery skin and ever-present sunglasses Bollettieri helped no fewer than 10 players who went on to be No. 1 in the world rankings.

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Australian coach and former player Darren Cahill wrote on twitter: “A pioneer, a visionary, a believer and a leader. Most importantly, a great coach and man that had time for anyone who loved tennis. RIP Nick. You will be missed by us all but remembered forever as a legend of our sport.”

Multiple champion Martina Navratliova tweeted: “RIP Nick- you were an amazing coach, transformed how tennis is taught and most of all, you were a very kind human being-it was an honor (sic) to have known you…”

Nick Bollettieri has passed away, aged 91. Credit: James A. Jones/AP

Born in New York in 1931 to Italian immigrant parents, Bollettieri was a paratrooper in the Army before enrolling in law school at the University of Miami.

In Florida he met Fred Perry, the British former grand slam champion, and decided his was a better lifestyle.

“I don’t want to be Perry Mason,” he said. “I want to be Fred Perry.”

He dropped out and switched to tennis coaching, initially watching other coaches in the park to learn how to do it.

“I didn’t know much about teaching the game,” he said. “The gift God gave me was the ability to read people.”

He became an itinerant coach working in Puerto Rico, Long Island, Wisconsin and elsewhere.

In 1978 he opened his tennis academy in Bradenton, Florida.

Nick Bollettieri and Andre Agassi in 1989. Credit: Caryn Levy/Sports Illustrated via Getty Images

Sports management giant IMG bought the academy nine years later but Bollettieri continued to oversee its tennis programme.

The site now has a boarding school, 55 tennis courts and facilities for seven other sports, including football, basketball and baseball.

Former world No.2 Tommy Haas, another Bollettieri success story and current tournament director of the BNP Paribas Open in Indian Wells, wrote on Instagram: “So many memories, I am not sure where to begin.

“Nickiiiii, that’s how I have called you for the longest time. Thank you for your time, knowledge, commitment, expertise, the willingness to share your skill, your personal interest in mentoring me, and giving me the best opportunity to follow my dreams.

“You were a dreamer and a doer, and a pioneer in our sport, truly one of a kind.”

An ebullient, effervescent character Bollettieri was still travelling to Wimbledon and working for the media deep into this 80s, in between playing golf and body-surfing on Florida’s Gulf coast.

Married eight times he had five children and, with his last wife Cindi, who survives him, adopted two more.

– AAP

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