Athletes, celebrities react to Muhammad Ali’s death

Ali was 74.

Muhammad Ali, legendary boxer and social activist, died Friday. He was 74.

Ali was hospitalized on June 2 to be treated for a respiratory issue. 

Ali was not only widely considered to be one of the greatest boxers, but his social activism and colorful personality also made him one of the most popular—and polarizing—athletes of all time. 

Ali, who was diagnosed with Parkinson’s disease in 1984, was born Cassius Clay. He joined the Nation of Islam in 1964, shortly after winning his first heavyweight title. Ali was arrested in 1967 for refusing to join the United States military. He appealed his case to the Supreme Court, which overturned his conviction in 1971. Ali would win the heavyweight title two more times before turning into a beloved figure in retirement. 

After news of his death, numerous athletes and celebrities paid tribute to Ali on Twitter.

• Muhammad Ali—boxing legend, activist, provocateur—dead at 74

God came for his champion. So long great one. @MuhammadAli #TheGreatest #RIP pic.twitter.com/jhXyqOuabi

— Mike Tyson (@MikeTyson) June 4, 2016

The Greatest. In boxing and in life, an inspiration to mankind. https://t.co/lfgd3H2gaT

— Gennadiy Golovkin (@GGGBoxing) June 4, 2016

#TheGreatesthttps://t.co/b3BnUTuxLd

— Team USA (@TeamUSA) June 4, 2016

It's been said it was Rope a dope, Ali beat me with no his beauty that beat me. Most beauty I've know loved him pic.twitter.com/G64WX3eyZC

— George Foreman (@GeorgeForeman) June 4, 2016

"The world has lost a great Champion. Muhammad Ali, lover of human beings, a warrior for the fight against discrimination...a great friend."

— Jim Brown (@JimBrownNFL32) June 4, 2016

We've lost a giant in Muhammad Ali. He did things his own way and I am so appreciative to have known him for so long. God rest his soul.

— Hank Aaron (@HenryLouisAaron) June 4, 2016

"If my mind can conceive it & my heart can believe it—then I can achieve it." Muhammad Ali taught us all to dream. pic.twitter.com/my6Cdw2p12

— Scottie Pippen (@ScottiePippen) June 4, 2016

Everyone in this picture acted like little schoolyard girls when The Champ walked into the room.. #TheGreatest pic.twitter.com/J2YT1UExom

— Reggie Miller (@ReggieMillerTNT) June 4, 2016

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Thinking of #MuhammadAli and remembering a man who was not afraid to take a stand and who was committed to being his authentic self.

— Billie Jean King (@BillieJeanKing) June 4, 2016

You'll always be The Greatest for more than just what you did in the ring. A champion to so many people in so many ways.

— Tiger Woods (@TigerWoods) June 4, 2016

He was unafraid to be his authentic self and in doing so became one of the greatest human beings ever. #RIPChamp pic.twitter.com/I21jf9y7ia

— Jason Collins (@jasoncollins98) June 4, 2016

He who is not courageous enough to take risks will accomplish nothing in life-- Muhammad Ali. #RIPAli

— Alex Morgan (@alexmorgan13) June 4, 2016

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Larger Than Life! RIP pic.twitter.com/yKi2KmwH5n

— Jimmy Graham (@TheJimmyGraham) June 4, 2016

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The Champ. Always. Forever.

Rest in peace, @MuhammadAli. #Legend pic.twitter.com/0BftMcNVbk

— Vontae Davis (@vontaedavis) June 4, 2016

Muhammad Ali The Greatest RIP LG x

— Liam Gallagher (@liamgallagher) June 4, 2016

His may be the Greatest of 20th century American stories. Muhammad Ali, rest In peace 1942-2016

— Neil deGrasse Tyson (@neiltyson) June 4, 2016

"It isn't the mountains ahead to climb that wear you out; it's the pebble in your shoe"
-Muhammad Ali #RIPMuhammadAli

— Chris Bosh (@chrisbosh) June 4, 2016

"He who is not courageous enough to take risks will accomplish nothing in life." - The Greatest, Muhammad Ali, R.I.P.

— Matt Harvey (@MattHarvey33) June 4, 2016

RiP to the one and only Muhammad Ali, simply the best...
Prayers 🙏🏾 up to his family and friends

— Vince Carter (@mrvincecarter15) June 4, 2016

Rest in peace @MuhammadAli #rip

— Kaka (@KAKA) June 4, 2016

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R.I.P CHAMP🙏🏼 pic.twitter.com/ZJEXfVisS4

— Book (@DevinBook) June 4, 2016

Ali is survived by his wife Lonnie and nine children.