Players' chief Gordon Taylor fears there will be more problems for managers like the one Roberto Mancini found himself dealing with in Munich last night as top clubs move towards a squad-based system.
Mancini has already stated his desire that Carlos Tevez should never play for Manchester City again after claiming the forward refused to warm-up during last night's 2-0 defeat to Bayern in the Allianz Arena.
Yet that was not the only sign of player unrest as Edin Dzeko also reacted poorly after being replaced by Nigel de Jong.
With players now on huge salaries and, in some instances, with egos to match, Taylor is concerned about their potential reaction to not being automatic first choice.
"I think a lot more players are going to get upset," he said.
"There will be top players not happy at being substituted, others who are not too pleased at being asked to retrieve a situation.
"But it is part and parcel of the game now.
"Players have to be professional, although sometimes managers have to be aware of the sensitivities involved too."
Taylor would be happy to get involved to try and resolve the situation should either party request it.
Such was the strength of Mancini's statements last night however that a peace deal seems highly unlikely.
In the first instance, Tevez is almost certain to be fined two weeks' wages - over £400,000 - with City chairman Khaldoon al-Mubarak then having the final say over what should happen next.
A January sale appears most likely, although given the wealth that is driving City's rise up the footballing ladder, the option of either cancelling the player's contract, or leaving him to rot in the reserves until the end of his present deal in 2014 cannot be ruled out.
"It is a serious situation," said Taylor.
"It wasn't a good thing to happen.
"It would have been difficult enough to accept if Manchester City had been winning. The fact they were losing 2-0 made it harder to understand.
"The owners of Manchester City clearly want a club with a good reputation. That was not the case last night.
"A statement has been made by Roberto Mancini that the player will not play for the club again. Now it is for the owners to deal with."Reuse content