It’s pretty obvious, before the quarterback throws the ball, when a given play is going to be a Hail Mary. This makes it somewhat enjoyable, when playing along at home, to cry “Haaaail” as the quarterback winds up and “Mary!” as he heaves the pigskin into the upper stratosphere.
I suppose it would be just as entertaining to cry “Alleeeeeey” and then “Oop!”, too. 
Let an old Cowboy fan hang his head in shame. I most certainly remember that Staubach-to-Pearson throw against Minnesota. (1974, right?) I actually did remember it yesterday when I mentioned Flutie, but I was SURE Flutie was the one who named it.
There was a Rockie & Bullwinkle cartoon, made in the 60’s where Bullwinkle threw the Rock like a football. Bullwinkle would say “Alley…” and let fly; Rocky would say “Oop!” while in flight. PERHAPS the producers made it up for the cartoon, but it’s more likely they heard about it from real games.
Those who do not learn from the past are condemned to relive it. Georges Santayana
Um, not to pick nits, mainly because I could well be wrong, but I think Rocky said Alley and Bullwinkle said Oop. Without Rocky saying Alley, Bullwinkle couldn’t throw very far, so of course Boris Badenov did something to Rocky so Whatsammat U. would lose the big game.
PUN
Man I HAVE to get a life someday.
Hey, haven’t you heard? This IS our life.
Those who do not learn from the past are condemned to relive it. Georges Santayana
jab1:
Not football. Gymnastics and the circus. It was a cry by a French gymnastic group (possibly apocryphal). The anchor would yell, "Allez! in French and the person being heaved up would yell Uuuup! in French-sounding English.
I’m not sure how the cartoon cave man got the name.
Tom~
Which only goes to show that there is no mistake so trivial that someone, somewhere won’t respond to it! 
Those who do not learn from the past are condemned to relive it. Georges Santayana
Hey, I just did my first italics and boldface. I’m so proud…
Those who do not learn from the past are condemned to relive it. Georges Santayana
Well, I sure didn’t mean to send this thing off that far on a tangent, but…
Now I’m confused. (not unusual) I stand corrected on the Immaculate Reception. But the thing is, I wasn’t watching football in '72, so I know I’d never heard that expression before. So there had to be something about that Lynn Swann play that referred to it, or something like that. It’s not all that important, but it’s got my curiosity going. I’m assuming it was a Steelers-Broncos game, because I can’t imagine I would have been watching the Steelers any other time. Any Pittsburgh football fans out there who can get this little nagging question out of my head?
Thanks much for the clarification and correction, Omni. I knew that there had been a rule change as a result of the bruhaha over that play, but it appears that I had it backward.
Reality is for people who can’t handle drugs.
-Tom Waits