Currently, you have the choice to throw a game, to mix up your minutes as best as you can to try to win all three games, or any combination thereof, depending on your assessment of which game(s) you can win or lose and how important you value each of the three games.
Unacceptable choices in a sim of athletic competition. In athletics one competes to win. In a sim of athletic competition it should be the same. This is not a game of athletic competition nor even the management of a competitive athletic team, as it purports to be. Anyone looking for a sim of athletic competition, such as basketball, will either be disappointed or accept that this game is something else entirely (as many have obviously done). Question: why on earth in a sim of athletic competition would there be issues of playing your players out of position, throwing games, tanking, etc.? Answer: there wouldn't be.
Look, I know you'd prefer the easy button mode where all you do is set one lineup and they play for you in perpetuity, and that therefore the team with the best roster (usually exactly equivalent to the most money and longest tenure) wins almost every time. But believe it or not, life isn't like that either - pitchers start one out of every four games, NHL goalies rarely if ever play both games of a back to back, European soccer (football) teams often play younger lineups in their Cup competitions and shuffle through more than their best XI plus five subs during the course of a couple weeks of competition.
But humor us: what does a "one lineup for every game" mode *ADD* to the game? How does it make it better, more fun, more challenging, more of anything other than placating your "everything has to make sense" fetish?