Bill Russell was 88.Russell died "peacefully" with his wife, Jeannine, at his side.

The statement did not give the cause of death, but Russell was not well enough to present the NBA Finals MVP trophy in June because of a long illness.

NBA commissioner Adam Silver called Russell "the greatest champion in all of team sports" in a statement Sunday.

Until Michael Jordan's exploits in the 1990s, Russell was considered by many as the greatest player in NBA history.

"Bill Russell was a pioneer -- as a player, as a champion, as the NBA's first Black head coach and as an activist," Jordan,said in a statement. "

"Russell was awarded the Medal of Freedom by former President Barack Obama in 2011, the nation's highest civilian honor.

Bill Russell was named the NCAA tournament Most Outstanding Player in 1955.

He then led the U.S. basketball team to victory in the 1956 Olympics at Melbourne, Australia.