Hi,
https://goalfc.net/match/replay/9670729

The replay from this game shows my M RC guy lined up in the wrong spot and I lost 0-3 in the European Cup Final.

I already had Ginja at M C, but from the start of the game, Fernandes was in MC as well, not M RC.

I’ve changed the players now, will see how Portugal’s next match goes.

That’s related to your positioning instructions, where the guy is instructed to move left when your team has the ball. Given your team started with the ball, he was to the left of where he should be. If you check the 45 mins mark, when lined up for second half start your player is positioned in M RC, as the other team has the ball.