What is 'The Immaculate Reception'? The controversy and how the famous NFL play got its name

Decades after the iconic play, there is still plenty of debate over whether Franco Harris' touchdown for the Pittsburgh Steelers was legit. These days instant replay would answer the questions surrounding the play.

Did the ball bounce off Oakland Raiders safety Jack Tatum and shoot back? Or was it Steelers running back John "Frenchy" Fuqua who deflected Terry Bradshaw's pass to Harris (an illegal "double touch" back then)? Did the ball nick the turf as Harris caught it?

"What makes the play great is the mystery of it," said Neil Zender, who produced a show on NFL Network around the 40th anniversary of the iconic play. Zender said that allows for personal interpretation: "The Raiders can see it as a crime, and the Steelers can see it as the hand of God."

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What is the Immaculate Reception? 

Dec. 23, 1972

In an AFC divisional playoff game, the Steelers trailed the Raiders 7-6 with 22 seconds left, facing fourth-and-10 at their 40-yard line. The primary receiver on the play was supposed to be rookie Barry Pearson, playing in his first game. After a scramble, Bradshaw threw down the middle to Fuqua at the Raiders 35 yard-line.  Fuqua and Oakland defensive back Jack Tatum collided, sending the ball careening back toward midfield in the direction of Harris, who snatched the ball just inches above the Three Rivers Stadium turf near the Oakland 45 before he outraced several stunned Raider defenders to score.

Harris' touchdown secured the Pittsburgh Steelers’ first-ever playoff win. The Steelers would go on to win four Super Bowl rings in six years.

"The official got in one of those huddles they have (after the play) and this was before instant replay. And then I ran out on the field," former Raiders coach and Hall of Famer John Madden said in a documentary about the play. "They say, 'We don't know what happened.' I say, 'I know you don't know what happened. I'll tell you what happened.' I said, 'It hit Frenchy Fuqua illegally, Frank Harris can't get it.' Well, they told me to get the hell off the field."

What were the rules surrounding the play? 

The rule then — which was removed in 1978 — was that if one offensive receiver was the first player to tip a pass, it couldn't legally be touched next and caught by another offensive player.

NFL Films rounded up all the visual evidence it could find, including its shots from up high at midfield and the Steelers end zone. NBC's full telecast of the game was lost. But the NBC shots of the play from high-midfield and from above and behind the play survived.

Tatum, who died in 2010, always said he never touched the ball. Former Raiders defensive back George Atkinson, who calls the play the Immaculate Deception, seconds that. "Jack Tatum hit (Fuqua) from behind into the ball," he told NFL Films.

NBC's end-zone shot shows the ball closing in on Tatum's right shoulder. In slow motion, it looks like Tatum touches the ball. But it's blurry, and the collision between Tatum and Fuqua is partially obscured by one upright of the goal post.

Did Harris catch the ball legally? 

"He caught it I'd say calf-high on the left side of his body," Art McNally, the former NFL supervisor of officials who was in the press box that day in Pittsburgh, told USA TODAY in a 2012 interview.

Former Raiders linebacker Phil Villapiano said Harris made a great catch.

Yet Bradshaw and Harris feed the mystery. "More than likely, he probably trapped it," Bradshaw said with a laugh in an NFL Network documentary.

What is Harris' take on whether it hit the ground?

"I can't say," he said with a shrug.

Why is it called the Immaculate Reception? 

"Dec. 23 will henceforth be celebrated in Pittsburgh as the Feast of the Immaculate Reception," legendary local sportscaster Myron Cope proclaimed.

According to the Associated Press, Cope got the idea from a caller whose boyfriend had coined the name in a barroom victory celebration – putting a twist on the recently passed Catholic Feast of the Immaculate Conception, which marks the belief that the Virgin Mary was conceived without sin.

How far did the Steelers make it in the playoffs after that?

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.

This article originally appeared on USA TODAY: The Immaculate Reception: How the famous NFL play got its name