NBA and its community are mourning after the news about Bill Russell's death emerged.

Russell's family released an official statement regarding the basketball star's passing, confirming that the NBA legend died with his wife, Jeannine, by his side.

"Bill's wife, Jeannine, and his many friends and family thank you for keeping Bill in your prayers. Perhaps you'll relive one or two of the golden moments he gave us, or recall his trademark laugh as he delighted in explaining the real story behind how those moments unfolded," part of the statement said, per CBS Sports.

It did not disclose Bill Russell's cause of death, but it divulged that the athlete passed away "peacefully" in his sleep.

Former POTUS Barack Obama also penned a message on Sunday to send his condolences to the bereaved family. He awarded the late basketball star the Presidential Medal of Freedom in 2011, the nation's highest civilian honor.

NBA commissioner Adam Silver, as shared by Shams Charania, called Russell "the greatest champion in all of the team sports."

"For nearly 35 years since Bill completed his trailblazing career as the league's first Black head coach, we were fortunate to see him at every major NBA event, including the NBA Finals, where he presented the Bill Russell Trophy to the Finals MVP," Silver went on.

What Made Bill Russell Become One of the Greatest NBA Players

The Louisiana native, initially, was not considered a top basketball prospect.

But from 1955 to 1956, he led the University of Francisco to national championships due to his basketball skills. Still, it was not enough for him to become the first pick in the 1956 NBA Draft.

Russell got the chance after Boston Celtics star Ed Macauley's son started receiving treatment for spinal meningitis, leading him to land the No. 2 pick.

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In 1980, he was hailed as the greatest player in NBA history for winning through the defense and rebounding, allowing his teammates to score instead.

After leaving the Celtics following the end of his basketball career, he worked as a television broadcaster before coaching the Seattle Supersonics. He then coached Sacramento Kings for one season a decade later.

Russell chose to stay out of the public eye in the years thereafter and lived his life in his home in Washington.

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