Bill Russell, the NBA and Boston Celtics great, was defined as an “an all-time champion of champions” by US President Joe Biden, who released a statement late Sunday. Russell’s family announced his death on Sunday. He was 88.

“Bill Russell is one of the greatest athletes in our history”, Biden wrote in a White House statement. “A good man and great American who did everything he could to deliver the promise of America for all Americans”, he added.

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Biden’s statement focused on two aspects of Bill Russell‘s life: His achievements as a basketball player and his advocacy for equal rights in America. A similar tribute was given by former US President Barack Obama, who gave a Presidential Medal of Freedom to Russell.

“From a childhood in segregated Louisiana to a career playing on the biggest stages in sports at the height of the Civil Rights Movement, Bill faced the hostility and hate of racism embedded in every part of American life”, Biden wrote.

Biden also mentioned that Russell joined Dr. Martin Luther King Jr. on August 28, 1963, when he delivered the popular “I have a dream” speech.

While speaking of Bill Russell’s achievements as a basketball player, Biden appreciated his 11 NBA championships in his 13 years, five regular season MVP awards, an Olympic gold medal and being the first black coach of any major sports league in America.

Also Read: Boston Celtics pay tribute to Bill Russell: ‘The greatest champion’

Russell said that when he was growing up in the segregated South and later California his parents instilled in him the calm confidence that allowed him to brush off racist taunts.

“Years later, people asked me what I had to go through,” Russell said in 2008. “Unfortunately, or fortunately, I’ve never been through anything. From my first moment of being alive was the notion that my mother and father loved me.”