Rest important players for big game, morale dips - realistic?

When Barcelona had already won the La Liga they put out their youth team in the last three games to rest the big players for the CL final. However, they went on to loose these games, and in FM that would probably mean a significant morale drop even for the rested, first XI players. I hardly think Guardiola would risk his teams morale IRL before such a big game and I think you should be able to tell your first XI something like "I'm gonna rest you for a big game, I'm not DROPPING you. And the upcoming league results are of no importance"

What do you say, any need for this? Any experiences on this matter at all?

From my experience, a couple of losses don't seriously affect the morale of those not playing. But they lose morale from not playing in matches anyway i think. There's a balance to be had between match fitness, morale, and resting players.

From my expericences a couple of losses do effect morale