The first time Aaron Rodgers completed a Hail Mary touchdown pass in the NFL his throw almost hit the ceiling of Detroit’s Ford Field. Videos shot from the stands and field show the Packers quarterback firing the ball so high it nearly grazed a support rafter before landing in the arms of tight end Richard Rodgers 66 yards away.

“I love how Aaron can get it into the end zone, but with that much height I was a little concerned,” Packers coach Mike McCarthy said that night in December 2015 after Rodgers’s Hail Mary gave Green Bay a last-second victory over the Detroit Lions.

And yet the fact Rodgers can propel the ball to such heights, launching it like a pigskin rocket, might be what has made him an expert at what is supposed to be a prayer of a pass. Three times in 13 months he has thrown Hail Marys for touchdowns making him, perhaps, the greatest Hail Mary quarterback in the history of pro football. Not that there is much competition for the title. His half-time Hail Mary in Sunday’s wildcard win over the New York Giants pushed him out of a four-way tie with Cincinnati’s Andy Dalton, former Browns quarterback Tim Couch and former Falcons star Steve Bartkowski for most Hail Mary touchdowns in NFL history.

Then again the word precise should not be used in conjunction with Hail Mary. The play’s name itself is a plea for a miracle, originally used by Notre Dame’s legendary Four Horsemen to describe any long, seemingly hopeless pass but has come to mean one final desperate throw of at least half-a-field with zeros on the clock. When the Hail Mary works, it is one of the most exciting plays in sports. It is also the most deflating for the team that gives it up because the touchdown usually comes at the end of the game or the end of a half. Rodgers’ pass on Sunday came just before half-time giving Green Bay an unexpected eight-point lead that broke the Giants.

With Rodgers and the Packers hitting so many in such a short time it’s easy to wonder if somehow they have discovered a Hail Mary secret.

In a sense they have.

Following Sunday’s victory over the Giants both Rodgers and receiver Randall Cobb, who caught the half-time Hail Mary, used an interesting word. Watching Rodgers pass fall toward the end zone it seemed as if New York’s players had misjudged the ball, they said. The slight error in predicting where it would land had allowed Cobb to slip undetected into the back of the end zone where he caught the ball so easily it looked as if he had been waiting for it all along.

“He’s throwing it and [opponents] are misjudging it,” Cobb said.

But it might be the very way Rodgers throws his Hail Marys that is causing confusion among other team’s defensive backs. In all three of his Hail Marys – the Detroit game, the end-of-regulation pass at Arizona in last year’s playoffs and on Sunday – the opposing players looked slightly off in their leaps for the ball. Rodgers said Sunday he throws his Hail Mary passes higher than other quarterbacks. The Ford Field heave is a great example. The balls go so high in the air they are more like punts than passes and catching a punt is hard enough without having to jostle with other players for position in the end zone.

“When it’s that high, it’s difficult to judge for receivers and defensive backs,” Rodgers said Sunday. “As there was a cluster, Randall slipped to the back.”

The difference between the Packers receivers and the teams they play is that the Green Bay receivers are used to Rodgers’s Hail Mary passes, having seen them in practice. Their opponents haven’t. That slight deviation is enough to let his team-mates make seemingly easy catches as defenders leap in the wrong place.

How high does Rodgers fling his Hail Mary? A few days after the 2015 game-winner in Detroit, Mike Reuter of the site Cheeseheadtv used math to explain the mechanics of Rodgers game-winning pass. He calculated that Rodgers threw the ball at an arm angle of 53 degrees, sending it flying at 57mph to a peak of 78 feet, travelling a total of 105 yards when accounting for the arc for 4.15 seconds. It’s hard to imagine another quarterback who can throw a ball as high or as far with similar accuracy.

As chaotic as they might seem, Hail Mary passes are not disorganized scrambles with the ball heaved into the middle. Teams actually script plays to score on such throws as well as design schemes to stop them defensively. McCarthy said the team works on Hail Marys each Saturday in their final practice of the week, though Rodgers said he hadn’t actually thrown a Hail Mary in practice since October.

“We practice it once a week but it’s more for the defense to try and break it up,” Cobb said.

Most coaches teach their defenders to knock passes to the ground rather than attempt an interception. The thinking is that when a defensive player tries to catch the ball he runs the risk of having it slip through his hands or bounce off his fingertips giving receivers a chance to grab the ball for a score.

When the Packers offensive players run Hail Mary drills they do so with assigned roles. Some drift to the middle of the end zone but one usually has the assignment of trying to get to the back of the end zone in case a pass goes over the defenders as Rodgers’s did on Sunday. Another player stands just in front of the goal line in case the ball goes slightly short of the pack. This is where Richard Rodgers was that 2015 night in Detroit.

On Sunday, Cobb’s job was to box-out Giants defenders and give receiver Davante Adams - the designated leaper - room to catch the pass. Instead, Cobb moved behind the players who misjudged the throw and found the ball dropping into his hands.

It might have looked like luck, but even good fortune can be the product of science.

Or a just a matter of watching a Hail Mary fly so high it must seem like it touches the heavens.