Pro Football Hall of Famer John Mackey, who helped revolutionize the position of tight end as an offensive weapon, died on Wednesday. He was 69 and had suffered from dementia for years.
Mackey played 10 seasons for the Baltimore Colts and San Diego Chargers, catching 331 passes for 5,236 yards and 38 touchdowns. As president of the NFL Players Association after the AFL-NFL merger, he fought to improve players' pension benefits and access to free agency.
Enshrined in 1992, Mackey was the second player elected to the Hall of Fame as a tight end. He played in five Pro Bowls and was named All-NFL at his position three times.
In a statement posted by NFL spokesman Greg Aiello on Twitter, commissioner Roger Goodell called Mackey "one of the great leaders in NFL history, on and off the field."
"He was a Hall of Fame player who redefined the tight end position. He was a courageous advocate for his fellow NFL players as head of the NFL Players Association," Goodell said. "He worked closely with our office on many issues through the years, including serving as the first president of the NFL Youth Football Fund. He never stopped fighting the good fight. Our thoughts are with Sylvia and the Mackey family on the loss of our good friend."
In a pair of Twitter entries, current NFLPA executive director DeMaurice Smith paid tribute to Mackey.
"John Mackey has inspired me and will continue to inspire our players. He will be missed but never forgotten" reads a post on Smith's Twitter page.
A previous post reads: "John Mackey is still a leader. As President of the NFLPA he led the fight for fairness with brilliance and ferocious drive."
He suffered from frontotemporal dementia in later years that is believed to have been caused by the contact associated with playing football. Four years ago, the dementia forced Mackey into living in an assisted-living facility. But the cost of his care well exceeded his pension of less than $2,500 a month.
His plight eventually led the NFL and the players' union to establish the "88 Plan" -- named for his uniform number -- providing for nursing home care and adult day care for retired players suffering from dementia or Alzheimer's disease.
In 2010, Sylvia Mackey pledged to donate her husband's brain upon his death to a Boston University School of Medicine study of brain damage in athletes. The university's Center for the Study of Traumatic Encephalopathy is researching potential links between repeated concussions and CTE, a condition which mirrors symptoms of dementia and Alzheimer's disease.
As the first president of the post-merger players' union, Mackey started fighting for improved salaries and benefits for players. In July 1970, he organized a players' strike that resulted in an additional $11 million in pensions and benefits, according to The Baltimore Sun.
Mackey also filed and won an antitrust lawsuit against the NFL which eliminated the so-called "Rozelle Rule," named for then-commissioner Pete Rozelle, which mandated equal compensation for teams that lost free agents and had the effect of limiting free-agent signings. The ruling set the stage for the players' union to eventually achieve full free agency.
"We were a fractured group until John began putting permanence in [the union's] day-to-day operations," said teammate and former union president Ordell Braase, according to The Sun. "He had a vision for that job, which was more than just putting in time and keeping the natives calm. You don't get anything unless you really rattle the cage."
Drafted in 1963 from Syracuse, Mackey, at 6-foot-2 and 224 pounds, helped revolutionize the position of tight end by bringing the added dimension of speed, forcing defenses to account for him not only as a blocker but as a breakaway threat.
"Previous to John, tight ends were big strong guys like [Mike] Ditka and [Ron] Kramer who would block and catch short passes over the middle," former Colts coach and fellow Hall of Famer Don Shula said, according to The Sun. "Mackey gave us a tight end who weighed 230, ran a 4.6 and could catch the bomb. It was a weapon other teams didn't have."
If Mackey did not run past defenders, he ran through them.
"Defensive backs fell off of him like gnats," said Baltimore Colts teammate Jerry Hill, according to The Sun. "John didn't have a fluid gait -- he looked like a plowhorse -- but you didn't want to touch him for fear of getting caught up in the wheels."
"Sometimes you had a sense that, given the option, John would rather run over you than outrun you," added former Colts teammate Bob Vogel, according to The Sun.
In 1966, six of Mackey's nine touchdown receptions came on plays of 50 yards or more. His speed led the Colts to use him as a kick returner in his rookie season.
He caught 35 passes for 726 yards and a career high 20.7-yard average as a rookie in 1963, when he was selected to the Pro Bowl.
Mackey also played a crucial role in the Colts winning Super Bowl V in 1971. His catch of a Johnny Unitas pass that had been deflected by two other players -- Colts receiver Eddie Hinton and Dallas Cowboys defender Mel Renfro -- went for 75 yards and a touchdown. The Colts won 16-13 on Jim O'Brien's 32-yard field goal with 5 seconds left.
Baltimore Ravens owner Steve Bisciotti and general manager Ozzie Newsome also offered their condolences on Mackey's passing.
"I was fortunate to get to know John and Sylvia personally, and I was struck by her love and loyalty throughout the difficult times of his illness," Bisciotti said. "John set the standard by which tight ends are measured on the field, and he will be sorely missed not only by his family, but also by the entire Baltimore community. "
"John revolutionized the tight end position during his Hall of Fame career, and he laid the foundation on and off the field for modern NFL players," Newsome added.
Syracuse named Mackey, who played for the Orange from 1960-62, to its all-century team in 1999 and retired his No. 88 in 2007. His legacy is remembered yearly when the John Mackey Award is bestowed upon the player deemed college football's best tight end.
ESPN national correspondent Sal Paolantonio and The Associated Press contributed to this report.