The players don't seem to care either and you can tell they are mentally weak.
Comments like that from MATS say a lot, it confirms the weak mentality shown in Rome and Liverpool has gotten so poisonous it affects players every game and not just their mentality but physically too.
Some players can be in a mentally indisposed state but it rarely or never happens collectively.
Lack of motivation is usually the culprit in these cases, but it's a matter that is largely on the coach's shoulder, as he is the one to actually motivate his team. Not one by one but collectively.
I've seen MATS comments, but frankly I wasn't truly persuaded by that. I think it was yet another attempt to take off the responsibilities from the coach's shoulder.
(It's a very simple mechanism, if you spread the responsibilities nobody will be taken as individually responsible. But the coach is responsible alone for everything, individually, thus by disseminating the weight, they wish to save the coach).
Psychologically speaking, an entire team can not be in the same state at a given moment, there will always be differences, specially that what we usually mean by psychology nowadays, is covering individual states, actions and reactions.
Along with the subs, 13-14 players can not be psychologically in a similar state, although they can be frightened, unmotivated, tired and things like that, still their mental state will hugely differ.
If the team went to the pitch at those important moments, by thinking it will not be difficult, they would score one goal somehow and the opposition will not score three times, it can be an underestimation of the situation, it can be lack of motivation but it has nothing to do with the psychological state of an entire team.
When tactics are missing or don't work out, players tend to behave like Suarez does, with the difference they rather swallow their inner imbalance and reactions.
When players come off the pitch feeling that they individually did well, only the others screwed up their chances or made huge mistakes, that is the moment when they start saying things like MATS did. They talk about collective responsibilities but make no mistake about it, they don't think it seriously for a second. Just the opposite of that: they are positive about they individually did their best and the mistakes of the others led to the unwanted result.