Tom Brady remembered Bill Russell as a sporting figure with "a great presence" as he recalled striking up a rapport with the Boston Celtics great, who died on Sunday.

NFL superstar Brady told a news conference about his sorrow at hearing of Russell's death at the age of 88.

He had come to know the basketball hero when living in the Boston area, while spending 20 seasons as quarterback with the New England Patriots.

Russell was drafted by the Celtics in 1956 and went on to win 11 NBA titles. He was a five-time NBA MVP and is one of only four players to have been named to all four NBA anniversary teams (25th, 35th, 50th and 75th).

He became the first black head coach of any North American professional sports team, leading the Celtics to back-to-back NBA championships in 1968 and 1969 when he served as a player-coach.

Russell also made a significant impact away from the basketball court, championing the civil rights movement, and Barack Obama awarded him the Presidential Medal of Freedom in 2011.

Brady said: "I knew him pretty well. I had a lot of time up there in Boston and got to know him and he was a very impactful figure.

"Going back to my early days with the Patriots, in my second year at training camp he came and spoke to the team.

"A really imposing figure, he had a great presence around him and obviously what he overcame in his career was pretty unbelievable. It was a sad day."

Chicago Bulls hero Michael Jordan on Sunday described Russell as a "pioneer" and a "legend", while Obama also paid tribute to "a giant".

The Celtics said Russell's "DNA is woven through every element" of the organisation.

Michael Jordan has hailed Bill Russell as a "pioneer" and a "legend", while the Boston Celtics and Barack Obama also paid glowing tributes to the basketball legend after he died on Sunday.

Russell's family announced that he had passed away peacefully at the age of 88.

One of the all-time greats, Russell won 11 NBA titles, was a five-time NBA MVP and is one of only four players to have been named to all four NBA anniversary teams (25th, 35th, 50th and 75th).

He was the first black head coach of any North American professional sports team, leading the Boston Celtics to back-to-back NBA Championships in 1968 and 1969.

Russell also made a huge impact off the court, championing the civil rights movement and Obama awarded him the Presidential Medal of Freedom in 2011.

The legendary Jordan said: "Bill Russell was a pioneer – as a player, as a champion, as the NBA's first black head coach and as an activist.

"He paved the way and set an example for every black player who came into the league after him, including me. The world has lost a legend. My condolences to his family and may he rest in peace."

The Celtics said Russell's "DNA is woven through every element" of the organisation.

"To be the greatest champion in your sport, to revolutionise the way the game is played, and to be a societal leader all at once seems unthinkable, but that is who Bill Russell was," the NBA franchise stated.

"Bill was a champion unlike any other in the history of team sports – an 11-time NBA champion, including winning eight consecutive titles, a five-time MVP, an Olympic gold medalilst and the NBA’s first Black head coach.

"Bill Russell's DNA is woven through every element of the Celtics organisation, from the relentless pursuit of excellence, to the celebration of team rewards over individual glory, to a commitment to social justice and civil rights off the court. 

"Our thoughts are with his family as we mourn his passing and celebrate his enormous legacy in basketball, Boston, and beyond."

Former United States president Obama posted on Twitter: "Today, we lost a giant.

"As tall as Bill Russell stood, his legacy rises far higher – both as a player and as a person.

"Perhaps more than anyone else, Bill knew what it took to win and what it took to lead. On the court, he was the greatest champion in basketball history. Off of it, he was a civil rights trailblazer – marching with Dr. King and standing with Muhammad Ali.

"For decades, Bill endured insults and vandalism, but never let it stop him from speaking up for what's right. I learned so much from the way he played, the way he coached, and the way he lived his life."