There are no doubt many decisions to be made every game. They all impact a game, but not as much as one would think. Here is what Mitchel Lichtman has to say on the topic:
Before you go ballistic when a manager makes a strategic error (you think) and his team loses presumably "because" of it........
It takes around 50 to 200 bad manager decisions (bullpen, pinch hitter, IBB, bunt, etc.) before he costs his team ONE win.
Here is an article that does a good job of explaining the impact of each managerial decision:
http://www.beyondtheboxscore.com/2015/10/21/9574081/the-impact-of-managerial-mistakes
And the summary of that article if you don't want to read the whole thing:
Again, I could keep going, but I hope the point is clear. When this game was happening, these felt like three pivotal decision points, where the game had the potential to be lost or won based in part on mistakes made by the manager. That's technically true, but as these three cases show, it's in very small part. Managerial tactics matter, but not much.