Bill Russell, one of the most renowned athletes in American team sports history, died Sunday at 88.

Future generations will be able to admire the Boston Celtics star for his achievements.

Excellent track record as an 11-time champion and the NBA's first Black head coach.

Magic Johnson, a fellow Hall of Famer, paid tribute to Russell Sunday afternoon via tweets.

"I am heartbroken to learn about the passing of the greatest basketball player the game has ever seen."

Johnson wrote, "Bill Russell is a legend, Hall of Famer and mentor, and my friend for more than 30 years,"

Johnson called Russell his idol, whom he looked up to on and off the court. He was kind to Russell. 

Unsurpassed center to pave the way for athletes to fight social injustice and inequality.

"Despite his many accomplishments, he was humble, a gentle giant, and a knowledgeable person.