Tennis coaching pioneer Nick Bollettieri passed away aged 91, it was announced Monday.

Bollettieri, the coach of 10 former World No. 1s, was a magnetic force in the tennis community known for his unmatched energy. Former players, including Andre Agassi, Tommy Haas, Chris Evert, Martina Navratilova and Billie Jean King, and other members of the tennis community took to social media Monday to share their condolences.

Our dear friend, Nick Bollettieri, graduated from us last night. He gave so many a chance to live their dream. He showed us all how life can be lived to the fullest…

Thank you, Nick 🙏🏼 pic.twitter.com/PhO36oPWpI

— Andre Agassi (@AndreAgassi) December 5, 2022

RIP Nick Bolletieri ; Aside from being the greatest coach ever, you were so kind to me, my parents, and my siblings… that meant more to me than anything, you had a big heart and a zest for living…❤️❤️❤️

— Chris Evert (@ChrissieEvert) December 5, 2022

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 to have known you… https://t.co/hwv4RLtEo5

— Martina Navratilova (@Martina) December 5, 2022

Our sport lost one of its most passionate coaches & advocates. Nick was always positive & was able to get the best out of everyone fortunate enough to work w/him.

Our thoughts & prayers go out to his family & team at the Academy.

May he rest in peace. https://t.co/svkmaNXdBd

— Billie Jean King (@BillieJeanKing) December 5, 2022

Saddened to hear about @NickBollettieri passing! I’ll miss his genuine smile, quick wit, kindness and positive attitude. Always brightened my day!❤️#RIPNickBollettieri 💔

— Tracy Austin (@thetracyaustin) December 5, 2022

I am very saddened by the loss of @NickBollettieri
The tennis family has lost someone very important today, someone who has made our industry grow and has opened opportunities for coaches and players.
We will remember the very special human being you were and will miss you.

— Patrick Mouratoglou (@pmouratoglou) December 5, 2022

RiP Nick u were absolute giant who helped generations of players 🙏🙏🙏🙏

— Brad Gilbert (@bgtennisnation) December 5, 2022

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 🥲https://t.co/YN9Dg1uZwL

— Darren Cahill (@darren_cahill) December 5, 2022

Lamento mucho la pérdida de @NickBollettieri una persona siempre muy amable conmigo y quien dejó una huella en el tenis para siempre. QEPD 🙏🏽💔 pic.twitter.com/IM1MBoxbwe

— Gabriela Sabatini (@sabatinigabyok) December 5, 2022

THANK YOU Nick ❤️
You have given so many children a place to work for their dream. Supporting them with your knowledge and the believe that anything is possible. I was fortunate to be one of them.
You’ve shaped the game of tennis
You will be dearly missed!
Rest In Peace Nicki🕊💔 pic.twitter.com/DBVdcBn12b

— Sabine Lisicki (@sabinelisicki) December 5, 2022

RIP Nick Bollettieri! 🕯😢🕊

— Nicolas Kiefer (@Nicolas_Kiefer) December 5, 2022

RIP @NickBollettieri,tennis savant,an inspiration to so many. You made my dream come true…I will forever love you. My respects to Jimy and the family🙏🏻

— Nicolás Pereira (@nicolaspereira) December 5, 2022

Last night I was saddened to get a call that my good friend NICK BOLLETTIERI tennis Hall of Famer passed. Nick was so special to my family as he played a key role in my girls Terri & Sherri getting scholarships for @NDWomensTennis . Loved his spirit for LIFE.Pls GOD May he RIP! pic.twitter.com/bwXrfMIRRZ

— Dick Vitale (@DickieV) December 5, 2022