While I'm not a fan of Maxperson's tone, I have to back him up here - this is incorrect.
The rules tell you whether a given action in play is legal. But the rules do not determine what actions will be taken, and so don't say what it going to happen at every point in the game. Football players have choices. Will the team run or pass the ball? That's what is happening in the game, but which they do is not determined by the rules.
The other way to think of this - Note that football is a game with an end condition that is typically separate from its win condition. A football game typically ends after a specified amount of time of play has passed. Only in the case of a tie does the game end become entwined with the win/loss condition.
Play a one-shot D&D session with a maximum length in time (we only have the game store space until 10 PM!), and we have the same "where to start and where to finish". But clearly, D&D doesn't tell us what is going to happen in between start and end... and neither does football.
Don't mistake "rules constrain actions" with "rules determine actions".
But, right there, you have created a one shot D&D game. That is a DIFFERENT game than a campaign. The rules of the game do not tell you how long a campaign should be. There are no real end conditions within the rules.
I'm not confusing constraint with determine. Not at all. In games, the rules CONSTRAIN actions. Your choice of actions is determined by the rules at every single point in time during a game. You cannot opt for a forward pass in football if you are on defense. What actions are taken at any given time don't affect the rules at all. Sure, players have choices during the game, but, as far as the GAME itself is concerned, every single one of those choices is constrained by the game itself.
RPG's don't work like that though. In a game, the rules tell you how to set up for play. You follow the steps of the game, A to B to C until the game concludes. The individual choices within A, B and C don't really matter as far as the game is concerned. The game doesn't care who wins or loses. The game simply progresses until the proscribed end point. But RPG's don't have steps to follow. They don't have an initial set up, nor do they have a concluding end point. Not within the rules. Setting up a one shot is adding rules to the game that aren't contained within the rules themselves. Which has been my point all along. You CANNOT play an RPG as it is written the way you can play EVERY other game. In EVERY other game, you follow the steps that the rules tell you to follow. RPG's do not have any proscribed steps. So, one group plays and never rolls a die, the other group plays and barely says anything more complicated than a grunt while repeatedly throwing dice.
Yet, we consider them to be playing the same game.
You are the ones who keep zooming in on the individual choices. They aren't really that important as far as the game is concerned. Whether you blitz or play zone matters to YOU, the player, but, the game? The game proceeds exactly as predicted - ball is snapped, play continues until the runner is stopped, start again.