Are results pre-determined before a ball is kicked?

[July Fourth]

I think the only way to prove that the games are NOT pre-determined is by getting a substitute player that substitutes an injured player and scores a goal or makes an assist, reason being would be the match engine would not be able to determine that would happen before kick-off because its a result of your manager interaction during mid-game.

Kevin Mensah injured in a match and I put Savage on in play and he scored, so that theory goes out the window.