It was changed before the 1974 season. Googling informs me that there were some even wilder variations in the early years:
NFL used to require that when you tackled a guy you had to be on top of him or end up on top. So if you knocked a guy down you had to jump on him. That must have been very strange.
Was there a US football rule in which the player had to touch the ground of the end zone with the ball after scoring a touchdown? I seem to have seen that quite a few times in movies and tv. If so, what would happen if you failed to do this?
ETA: Holy crap, I just realized that this would be a literal touchdown! I never even wondered why it was called that.
That was required in football, the way it still is in rugby. It’s where the spike comes from. I don’t know what happened if you didn’t do it, if anything.
Was the defense allowed to try to stop you even after the ball crossed the goal-line? If so, This would be a completely distinct skill for goal-line defenders.
If you go way back a FG was worth more points than a touchdown.
Way, way, way back, ice hockey was a seven-man game. There were the goalie, three forwards, and two defencemen as today (although back then the defence were called the “point” and the “cover point”). There was also a rover, who didn’t have a set position, instead skating all over the ice, going where needed.
Long ago, Pitchers in baseball used to have to throw underhanded, to the spot where the batter requested them to throw. I miss that.
In Rugby League and Union you can hold the ball up in a tackle preventing a try, as the ball needs to be grounded cleanly.
LOL, try being a junior coach when they all want to play like Bron Bron!:mad:
What are you, 135? 
I miss…
Hockey players being allowed to go helmetless
Basketball players being allowed to go tattooless
Pitchers batting in both leagues
Football and hockey being allowed to end in ties (of course, they rarely happen in the NFL)
A pass incompletion having to at least have the pretense of reality (no spiking)
The two-line pass in the NHL
Jump balls before the alternate possession rule
Hoops used to have a jump ball after every made basket. Talk about slowing down the game.
Cricket has rules?
Wow … who knew 
I miss when all pitchers were actually in the batting lineup.
It was called securing the tackle. When he was knocked down, you had to show you were in front and he had no way to go. If a tackler was on your back, you could crawl with him.
You missed when guys who were terrible athletes would come up and swung in the general direction of the pitch. You must also miss the fact that they would not pitch to the guy in front of the pitcher giving you 2 dead spots in every lineup. It was horrible. The DH is genius.It gets action in the game and more runs. It gives guys who are not great runners that can hi,t a career . It extends careers of players who may be hall of famers.
Whats not to like?
And the rule against playing defense against the leagues favored stars. Fouls for showing up on the same court as Lebron or Jordon. Basketball reffing has made the game ugly.
This. I hate the college/HS football OT rules, and the hockey shootout. Ties weren’t so bad.
I don’t know about ties being all that rare before 1974, bob. As per pro-football-reference.com
Ties - Year
7 - 1973
5 - 1972
8 - 1971
9 - 1970 (3 involved the Chargers, in a 14 game season)
8 - 1969 (NFL + AFL pre merger)