49ers Ahmad Brooks said "...that was a big call in the game, and then we lost the game, and that's probably the reason why."
So let's pretend that call was not made and the 49ers take over at the Saints 46 yard line with 3:12 left in the game. The Saints have all 3 times outs left.
We don't really have to pretend because we know what happened when the 49ers did get the ball back. They moved the ball a whole 6 yards and only took 21 seconds off the clock.
The Saints got the ball with 1:41 and 1 time out. They go right down the field and kick a game-winning field goal.
If the flag was never called the Saints would have got the ball back with 2:51 left. There's not guarantee that the Saints don't go down the field and score a touchdown and use up all 2:51 and game over. Saints win.
Best case scenario for the 49ers would have been that the game would have gone into OT.
The only real play you can say decided the outcome was the field goal that was kicked with time expiring. Obviously if Harley misses, the 49ers win.
There's a ton of "ifs" in every game. If they call Kap for intentional grounding the Saints get a Safety and are ahead by 2 points and get the ball back with 1:56 left and the 49ers only have 1 timeout left. Saints win.
If they don't hit Sproles on the fair catch the Saints might not have enough time to make it down the field to kick the game winner. Niners win.
If Lance Moore doesn't muff that punt, if Cory White doesn't fumble into the endzone for a touch-back, if Gore doesn't drop that pass with 7 min in the 4th, etc, etc.