This game is not so easy when it comes to dividing minutes properly. I myself also had some surprises in the past with back-ups and starting players and stuff.
As said, fouls can be 1 disturbing factor, but even without foul trouble it is not that easy.
If you start a player, and his back-up is obviously better, it happens that the coach has the back-up play much more minutes, just because he is better and the coach wants the best on the field.
Then, if you are ahead with many points, the system changes, and your coach will put in your back-ups to spare your starters, thus putting that back-up on the court all the time.
This can happen, even if your starter did not get into foul trouble.
Therefor it is important to try to find out how your coach reacts to each tactic (fast or slow offense), and opposing team strength. If you predict you will lead with big points at the start of the 4th Q, you might best put the players who need most minutes as back-ups, not as starters...
It's not easy, and we all have trouble with it...
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