No one in the history of North American team sports won at a higher level than Bill Russell did as a member of the Boston Celtics, capturing 11 championships in his 13 seasons with the team.
Following his passing on Sunday at 88, tributes poured in fast and furious for the legend, from former President Barack Obama to the Celtics, the NBA community and fans, and politicians in Massachusetts.
A trio of current Celtics were among the first to offer their condolences, including Jayson Tatum, Jaylen Brown and Grant Williams.
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Marcus Smart also reacted to the news, saying Russell played and dominated in a day and league that was definitely "not soft." He called Russell "Celtics to the core."
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The Celtics issued a team statement Sunday mourning his passing and celebrating his "enormous legacy in basketball, Boston, and beyond."
"Bill Russell's DNA is woven through every element of the Celtics organization, 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."
"To be the greatest champion in your sport, to revolutionize 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 team wrote. "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 Medalist and the NBA’s first Black head coach."
Russell briefly coached the Seattle SuperSonics for four seasons and Sacramento Kings for one after retiring as a player.
Brad Stevens, the Celtics former head coach who now serves as the team's president of basketball operations, was saddened to hear the news of Russell's death, saying he set the standard on and off the court.
"RIP to an all-time winner, teammate and person," Stevens wrote in a tweet.
Wyc Grousbeck, Steve Pagliuca and the Boston Celtics ownership group also released a brief statement saying Russell "embodied character and commitment and he was truly one of the finest people to ever live."
"He will be remembered forever and deservedly so."
Celtics legend Paul Pierce, third in team history in win shares after Russell and Larry Bird, thanked Russell for being a trailblazer and pioneer who set the bar.
"I can go on all day about what [you] meant to me," Pierce wrote of Russell on Twitter. "Today is a sad day for the NBA family. [You] will be forever missed #6."
NBA commissioner Adam Silver issued a statement which touched on Russell's accomplishments not only on the court, but off of it as well, where he fought vigorously for civil rights and social justice.
"The countless accolades that he earned for his storied career with the Boston Celtics -- including a record 11 championships and five MVP awards -- only begin to tell the story of Bill's immense impact on our league and broader society," Silver wrote. "Bill stood for something much bigger than sports: the values of equality, respect and inclusion that he stamped into the DNA of our league."
"Through the taunts, threats, and unthinkable adversity, Bill rose above it all and remained true to his belief that everyone deserves to be treated with dignity," Silver continued.
The NBA commissioner added that Russell passed that legacy down to generations of NBA players who have followed in his footsteps.
"Bill was the ultimate winner and consummate teammate, and his influence on the NBA will be felt forever."
Obama, who presented Russell with the Presidential Medal of Freedom in 2011, noted how Russell endured insults and vandalism for decades -- but he never let it stop him from speaking up for what's right.
"As tall as Bill Russell stood, his legacy rises far higher -- both as a player and as a person," Obama said in a statement.
"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," Obama added. "I learned so much from the way he played, the way he coached, and the way he lived his life. Michelle and I send our love to Bill’s family, and everyone who admired him."
Russell won a pair of state championships in high school at McClymonds in Oakland, California, followed by two more NCAA titles at the University of San Francisco and then 11 with the Celtics -- including two as a player/coach in addition to one gold medal with Team USA at the 1956 games in Melbourne, Australia.
Following his trailblazing career, Russell was often seen at major NBA events, including the NBA Finals where he presented the Bill Russell Trophy to the Finals MVP.
In Massachusetts, there was reaction from the governor, Sen. Elizabeth Warren, and Boston's mayor, as well as the Boston Red Sox, Boston Bruins, and New England Patriots.
Gov. Charlie Baker said Boston and Massachusetts were lucky to be a part of Russell's life story, calling him the greatest of all time.
"Bill Russell was the definition of a legend," Baker wrote on Twitter. "He was a consummate winner and a trailblazer who broke barriers in the game of basketball and the game of life for Black athletes and Americans throughout his career and life."
Mayor Michelle Wu said Russell gave so much to the city of Boston, "as the greatest sports champion of all time & a role model fighting for justice, equality & labor rights."
"We owe him a debt of gratitude & we will miss him," Wu added in a tweet.
Warren called Russell "a legend on and off the court," also noting how he was a "trailblazer for justice and equality."
"My heart goes out to his loved ones as we all honor his powerful legacy and look to his example," the senator wrote on Twitter.
The Red Sox, who played a home game versus the Milwaukee Brewers on Sunday, held a moment of silence at Fenway Park.
"Bill Russell gave so much to Boston," the Red Sox wrote on Twitter. "He is a legend in every sense."
With the tweet, the team shared a picture of the ballpark as it asked fans to join them in honoring Russell, whose picture was displayed on the main video board.
“Bill Russell epitomized the success that we aspire to achieve - a quintessential champion who used his platform to stand up to the injustices of society and advocate for those whose voices are not always heard. His lifelong dedication to helping young children find mentors motivated us to develop the Red Sox Mentoring Challenge in his honor, and his strength in combating racism as a civil rights leader continues to resonate today," the Red Sox wrote.
"Our hearts are heavy as we send our deepest condolences to the Russell family. Please know that the fire that burned so bright in him will continue to inspire us at Fenway Park.”
The Boston Bruins extended its condolences to the Celtics and said the organization mourned Russell's passing. Nearby in Foxboro, the Patriots said Russell's impact extends far beyond Boston sports.
Celtics radio analyst said the death of his friend and mentor leaves a huge hole for us all.