The world of football does not tend to be your first port of call for sober reflection on life. In an industry that can so often be brash, where television companies jostle for attention and matches are billed like blockbusters, and where the players on the stage are trained to speak in hollow soundbites with which to bat away searching questions, it is rare to hear real candour.

Since arriving at Manchester United, however, Jose Mourinho has appeared somewhat subdued, even morose. There was the interview in which he bemoaned his personal living arrangements, with the startling headline that his life was ‘a disaster.’ Then there is his overall demeanour, which is glum where it once was bristling with energy, weary where once it seethed.

Many are claiming that Mourinho is a spent force and that United hired him too late. Yet it was not his own career that the Portuguese was speaking of when he said, after his team threw away a 1-0 lead against Arsenal on Saturday, “It is very sad to know that time flies for every one of us.”

Such observations, for the more contemplative among us, can really hit a nerve. For so much of life is tinged with sadness, nostalgia forever creeping up and laying its velvet-gloved hand on even our happiest memories, constantly reminding us that nothing lasts forever, life is fleeting, and things fall apart.

Football, as Mourinho’s remarks attest, is not immune. On the contrary, in fact, football offers almost constant reminders that time waits for no man and periods of plenty should not be taken for granted. He could have been speaking about any number of things in relation to his new club, which has been struggling for identity since Sir Alex Ferguson retired. The demise of Wayne Rooney, perhaps, who is currently experiencing his own existential crisis, more often than not from the sidelines, a once mighty force now reduced to the role of an extra in a play, the ravages of time having caught up with him with the stark, brutal force that only time can.

Rooney played well when coming off the bench on Saturday, yet it was not he who Mourinho was referring to either. Nor was he addressing those who argue that his own time at the top has been and gone. He was, in fact, talking about Michael Carrick who, like Rooney, has spent more time than he would like on the outside looking in this season.

“I always loved him but, instead of being his manager when he was twenty-four, I am his manager when he is thirty-five,” Mourinho bemoaned. For a while, this term, it appeared that Mourinho saw Carrick as surplus to requirements, barely picking the Geordie for whom Manchester has been home for over a decade. Recently, however, Carrick has had something of a mini-renaissance, with his new manager finally realising that the poise he still provides in abundance continues to be a potent, if subtle, weapon on the field of play.

Football is a constantly evolving game and, in these days of high-energy high-pressing, the relatively sedate nature of Carrick’s game can feel a little out-dated. Yet, as with Roy Keane and Paul Scholes before him, United are finding it difficult to move on from Carrick.

Keane, all these years later, has still never really been replaced, and Carrick, who took the Irishman’s shirt number when he was signed from Tottenham Hotspur in 2006, has been dogged by this fact throughout his United career. His elegant, patient style was always worlds away from Keane’s ferocious, energetic game. Thus, those who thought they were getting a like-for-like replacement were sorely disappointed and have always eyed Carrick with the suspicion that he is little more than a diet version of his predecessor; Roy Keane-lite, if you will.

Yet Carrick’s contribution to the club cannot be overstated and, as is so often the way, it is only now, when his powers are diminishing in the winter of his career, that many are coming to realise just what Scholes meant when he described him as a ‘Rolls Royce’ of a footballer. As understated as he is, Carrick’s purring play and magnificent reading of the game has been of huge influence over the years, as he has left the glory and the headlines to others while quietly going about his job with mesmerising consistency.

Now Mourinho appears to have noticed Carrick’s whispered mastery and realised that the likes of Paul Pogba, the bustling, roaring polar opposite of Carrick himself, can benefit from time spent under his protective, unruffled wings, even hinting at the possibility of another contract extension for a player whose time at the club, even just a few weeks ago, appeared to be up.

Many will see Carrick’s more regular inclusion in the team as a regressive step. Yet, in a world that moves so fast, where we rush so much and reflect so little, surely we should be happy to squeeze the last remaining drops from a player who has won it all and never really got the credit he has so thoroughly deserved.

Who eventually replaces Carrick is a question for the near future. The fact that the task is proving so difficult suggests that, like Keane and Scholes before him, he may just be one of those rare footballers who proves to be almost irreplaceable. Let’s enjoy him while we still can, for time is fast catching up with him, and we will miss him when he’s gone.