If you are playing a bot or a really week team(like you are this week) then play some back ups and a sprinkle in a starter or two who hasn't played as many minutes and TIE the game. You should win, your enth. should go up and you shouldn't have a huge drop in GS.
If you are playing a team that is capable of defeating you, then it is time to make a decision. You could (1)ruin your Game Shape and try to win the game with your regular players; (2) you could throw(intentionally lose by removing regular starters and TIE'ng) one of your league games and go for the cup win. or (3) if you don't value the cup, you throw the cup game and TIE it, improving your enth in the process.
The cup(for teams who have no shot at winning) is a chance at making extra money, that's all.
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