PITTSBURGH (AP)The ball fluttered in the air and all but one of the 22 players on the Three Rivers Stadium turf on that cold December day 50 years ago essentially stopped.

Franco Harris never did.

The Pittsburgh Steelers running back kept right on going, the instincts that carried him through his life both on and off the field during his Hall of Fame career taking over, shifting the perception of a moribund franchise and a reeling region in the process.

The Steelers rarely won before his arrival in 1972. The moment his shoe-top grab eternally known as the ”Immaculate Reception” entered the lexicon, they rarely lost.

Harris, whose heads-up thinking authored the most iconic play in NFL history, has died. He was 72. Harris’ son, Dok, told The Associated Press on Wednesday that his father died overnight. No cause of death was given.

His death comes two days before the 50th anniversary of the play that provided the jolt that helped transform the Steelers from also-rans into the NFL’s elite, and three days before Pittsburgh is scheduled to retire his No. 32 during a ceremony at halftime of its game against the Las Vegas Raiders. Harris had been busy in the run-up to the celebration, doing media interviews Monday to talk about a moment to which he is forever linked.

”It is difficult to find the appropriate words to describe Franco Harris’ impact on the Pittsburgh Steelers, his teammates, the City of Pittsburgh and Steelers Nation,” team President Art Rooney II said in a statement. ”From his rookie season, which included the Immaculate Reception, through the next 50 years, Franco brought joy to people on and off the field. He never stopped giving back in so many ways. He touched so many, and he was loved by so many.”

Even in retirement, Harris remained a fixture in the community and a team whose standard of excellence began with a young kid from New Jersey who saw the ball in the air and kept on running. It wasn’t uncommon for Harris to stop by the Steelers’ practice facility to chat with players who weren’t even born before his fateful play.

”I just admire and love the man,” coach Mike Tomlin said. ”There’s so much to be learned from him in terms of how he conducted himself, how he embraced the responsibilities of being Franco for Steeler Nation, for this community … He embraced it all and did it with such grace and class and patience and time for people.”

Harris ran for 12,120 yards and won four Super Bowl rings with the Steelers in the 1970s, a dynasty that began in earnest when Harris decided to keep running during a last-second heave by Pittsburgh quarterback Terry Bradshaw in a playoff game against Oakland in 1972.

With Pittsburgh trailing 7-6 and facing fourth-and-10 from its own 40-yard line and 22 seconds remaining in the fourth quarter, Bradshaw drifted back and threw deep to running back Frenchy Fuqua. Fuqua and Oakland defensive back Jack Tatum collided, sending the ball careening back toward midfield in the direction of Harris. Game officials weren’t sure who deflected the pass; replays were inconclusive.

While nearly everyone else on the field stopped, Harris kept his legs churning, snatching the ball just inches above the turf near the Oakland 45, then outracing several stunned Raider defenders to give the Steelers their first playoff victory some four decades after founder Art Rooney Sr. brought the still-fledgling NFL to western Pennsylvania.

”That play really represents our teams of the ’70s,” Harris said after the ”Immaculate Reception” was voted the greatest play in the league’s first 100 years in 2020.

Though the Raiders cried foul in the moment, over time they somewhat embraced their role in NFL lore. Oakland linebacker Phil Villapiano, who was covering Harris on the play, even attended a 40th-anniversary celebration of the play in 2012, when a small monument commemorating the exact location of Harris’ catch was unveiled. Villapiano still plans to attend Saturday night’s jersey retirement ceremony for his former rival-turned-friend, and is just fine with the mystery that still surrounds what actually happened at 3:29 p.m. on Dec. 23, 1972.

”There’s so many angles and so many things. Nobody will ever figure that out,” Villapiano said. ”Let’s let it go on forever.”

While the Steelers fell the next week to Miami in the AFC championship, Pittsburgh was on its way to becoming the dominant team of the 1970s, twice winning back-to-back Super Bowls, first after the 1974 and 1975 seasons and again after the 1978 and 1979 seasons.

And it all began with a play that shifted the fortunes of a franchise and, in some ways, a region.

”It’s hard to believe it’s been 50 years, that’s a long time,” Harris said in September when the team announced it would retire his number. ”And to have it so alive, you know, is still thrilling and exciting. It really says a lot. It means a lot.”

Harris, a 6-foot-2, 230-pound workhorse from Penn State, found himself in the center of it all. He churned for a then-record 158 yards rushing and a touchdown in Pittsburgh’s 16-6 victory over Minnesota in Super Bowl IX on his way to winning the game’s Most Valuable Player award. He scored at least once in three of the four Super Bowls he played in, and his 354 career yards rushing on the NFL’s biggest stage remains a record nearly four decades after his retirement.

”One of the kindest, gentlest men I have ever known,” Hall of Famer Tony Dungy, a teammate of Harris’ in Pittsburgh in the late 1970s, posted on Twitter. ”He was a great person & great teammate. Hall of Fame player but so much more than that. A tremendous role model for me!”

Born in Fort Dix, New Jersey, on March 7, 1950, Harris played collegiately at Penn State, where his primary job was to open holes for backfield mate Lydell Mitchell. The Steelers, in the final stages of a rebuild led by Hall of Fame coach Chuck Noll, saw enough in Harris to make him the 13th overall pick in the 1972 draft.

”When (Noll) drafted Franco Harris, he gave the offense heart, he gave it discipline, he gave it desire, he gave it the ability to win a championship in Pittsburgh,” Hall of Fame wide receiver Lynn Swann said of his frequent roommate on team road trips.

Harris’ impact was immediate. He won the NFL’s Rookie of the Year award in 1972 after rushing for a then-team-rookie record 1,055 yards and 10 touchdowns as the Steelers reached the postseason for just the second time.

The city’s large Italian-American population embraced Harris immediately, led by two local businessmen who founded what became known as ”Franco’s Italian Army,” a nod to Harris’ roots as the son of an African-American father and an Italian mother.

Though the ”Immaculate Reception” made Harris a star, he typically preferred to let his play and not his mouth do the talking. On a team that featured big personalities in Bradshaw, defensive tackle Joe Greene and linebacker Jack Lambert among others, the intensely quiet Harris spent 12 seasons as the engine that helped Pittsburgh’s offense go.

Eight times he topped 1,000 yards rushing in a season, including five times while playing a 14-game schedule. He piled up an additional 1,556 yards rushing and 16 rushing touchdowns in the playoffs, both second all-time behind Emmitt Smith.

Despite his gaudy numbers, Harris stressed that he was just one cog in an extraordinary machine that redefined greatness.

”You see, during that era, each player brought their own little piece with them to make that wonderful decade happen,” Harris said during his Hall of Fame speech in 1990. ”Each player had their strengths and weaknesses, each their own thinking, each their own method, just each, each had their own. But then it was amazing, it all came together, and it stayed together to forge the greatest team of all times.”

Harris also made it a habit to stick up for his teammates. When Bradshaw took what Harris felt was an illegal late hit from Dallas linebacker Thomas ”Hollywood” Henderson in the second half of their meeting in the Super Bowl following the 1978 season, Harris basically demanded that Bradshaw give him the ball on the next play. All Harris did was sprint up the middle 22 yards – right by Henderson – for a touchdown that gave the Steelers an 11-point lead they would not relinquish on their way to their third championship in six years.

Despite all of his success, his time in Pittsburgh ended acrimoniously when the Steelers cut him after he held out during training camp before the 1984 season. Noll, who leaned on Harris so heavily for so long, famously answered ”Franco who?” when asked about Harris’ absence from the team’s camp.

Harris signed with Seattle, running for just 170 yards in eight games before being released in midseason. He retired as the NFL’s third all-time leading rusher behind Walter Payton and Jim Brown.

”I don’t even think about that (anymore),” Harris said in 2006. ”I’m still black and gold.”

Harris remained in Pittsburgh following his retirement, opening a bakery and becoming heavily involved in several charities, including serving as the chairman of ”Pittsburgh Promise,” which provides college scholarship opportunities for Pittsburgh Public School students.

”I think everybody knows Franco, not just for the work he did on the field but off the field,” Steelers defensive lineman Cam Heyward said Wednesday. ”I think he was there making change, being involved in everything he could.”

Harris is survived by his wife, Dana Dokmanovich, and son Dok.

AP Pro Football Writer Josh Dubow in San Francisco contributed to this report.

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