His family posted the news on social media, saying Russell died with his wife, Jeannine, by his side. The statement did not give the cause of death.

“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,” the family statement said. “And we hope each of us can find a new way to act or speak up with Bill’s uncompromising, dignified and always constructive commitment to principle. That would be one last, and lasting, win for our beloved #6.”

NBA Commissioner Adam Silver said in a statement that Russell was “the greatest champion in all of team sports.”