Roy Keane’s comments on Jose Mourinho’s fixture complaints last week might have caused a stir, but it’s worth considering the former Manchester United captain was speaking from personal experience. These are Keane’s words from his first autobiography about the triumphant 1998-99 treble campaign, when his side ended up playing 63 games, a figure that would be one fewer than United’s this season if they do reach the Europa League final.

“You enter the concentration zone, live for the game and its attendant responsibilities to the exclusion of almost everything else,” Keane wrote. “Football is all-consuming. For a Manchester United player, perpetually chasing results and trophies, there is no respite. It’s a selfish existence. Wonderful, yes, exacting…”

Those comments also echo a recent column by Jamie Carragher about an even more relevant situation, when Liverpool were going for the treble of the old Uefa Cup and both domestic knock-out trophies. “The buzz we had in 2000-01 was unique," the former defender wrote. "That campaign was like nothing I ever experienced for the intensity that seemed to surround every fixture.”

That “buzz” and “wonder” are a world away from the weariness Mourinho has seemingly constantly displayed about United’s current schedule. Far from publicly firing up his players with the idea they are on the brink of something brilliant, he is now talking up the prospect of mental fatigue. You could fairly wonder about the effect that has on his squad’s mood, except the entire issue throws up a lot more questions. There is a middle ground here.

If Mourinho is mostly indulging in his typical expectation-management, but does have a point about how the English authorities treat Premier League clubs in Europe, he is also not the only one talking about it. It feels like the number of fixtures you have, and especially the absence of continental football, has become a more pronounced theme than ever before.

Middlesbrough 1 Manchester United 3 player ratings Show all 22 1 /22 Middlesbrough 1 Manchester United 3 player ratings Middlesbrough 1 Manchester United 3 player ratings Victor Valdes – 5 out of 10 His double save was a moment of excellence, but he was beaten twice by Fellaini and Lingard and conceded a calamitous third. AFP/Getty Images Middlesbrough 1 Manchester United 3 player ratings Antonio Barragan – 5 out of 10 Held his shape well at the back, but was beaten by the occasional over the top ball. Getty Images Middlesbrough 1 Manchester United 3 player ratings Bernardo Espinosa – 3 out of 10 Really struggled against the pace of Rashford and the other United forwards. An afternoon to forget. AFP/Getty Images Middlesbrough 1 Manchester United 3 player ratings Ben Gibson – 5 out of 10 Tried in vain to start attacks by hitting long-passes forward but had a difficult afternoon. Getty Images Middlesbrough 1 Manchester United 3 player ratings Fabio – 6 out of 10 Looked assured in possession and did well going forwards; one of Middlesbrough's better players. Getty Images Middlesbrough 1 Manchester United 3 player ratings Marten De Roon – 5 out of 10 He worked relentlessly, but ultimately failed to make an impact on the game. He was outplayed in the midfield. AFP/Getty Images Middlesbrough 1 Manchester United 3 player ratings Adam Clayton – 4 out of 10 He looked lost at times – drifting in and out the game. Lost possession quickly and failed to read the game. Man Utd via Getty Images Middlesbrough 1 Manchester United 3 player ratings Grant Leadbitter – 6 out of 10 Was a key element to almost every Boro move – making clever and quick decisions in possession. Getty Images Middlesbrough 1 Manchester United 3 player ratings Stewart Downing – 5 out of 10 Wasteful in possession and failed to make an impact going forward. Getty Images Middlesbrough 1 Manchester United 3 player ratings Alvaro Negredo – 5 out of 10 Was Middlesbrough's principal target man but he was always surrounded by a sea of United shirts. Getty Images Middlesbrough 1 Manchester United 3 player ratings Gaston Ramirez – 6 out of 10 Caused a nuisance of himself, but was guilty of dropping too deep at times. Getty Images Middlesbrough 1 Manchester United 3 player ratings David De Gea – 5 out of 10 Had very little to do. Unfortunate with Middlesbrough's goal. Getty Images Middlesbrough 1 Manchester United 3 player ratings Eric Bailly – 5 out of 10 Ramirez was getting the better of him at times due to his slack man-marking. Getty Images Middlesbrough 1 Manchester United 3 player ratings Chris Smalling – 6 out of 10 Intercepted a handful of important crosses and led the United defence well. Could have done better to clear the ball for Gestede’s goal. Getty Images Middlesbrough 1 Manchester United 3 player ratings Phil Jones – 5 out of 10 Held his own at the back, but made a number of unnecessary fouls. Getty Images Middlesbrough 1 Manchester United 3 player ratings Ashley Young – 6 out of 10 His assist for the opening goal was an example of his ability, although he drifted out of the game late on. Man Utd via Getty Images Middlesbrough 1 Manchester United 3 player ratings Michael Carrick – 6 out of 10 A textbook Carrick display. He created chances, defended well and his work rate was relentless. AFP/Getty Images Middlesbrough 1 Manchester United 3 player ratings Marouane Fellaini – 7 out of 10 Opened the scoring for United with a header. Tough tackling and used possession well throughout. Getty Images Middlesbrough 1 Manchester United 3 player ratings Antonio Valencia - 5 out of 10 Defended well, but looked even better going forward to support the strikers. Getty Images Middlesbrough 1 Manchester United 3 player ratings Juan Mata – 7 out of 10 Looked dangerous going forward and classy on the ball. Getty Images Middlesbrough 1 Manchester United 3 player ratings Jesse Lingard – 7 out of 10 His goal was an example of his individual ability – fully deserved. He linked well with Rashford throughout. Getty Images Middlesbrough 1 Manchester United 3 player ratings Marcus Rashford – 6 out of 10 Should have scored, especially in the first half. Worked well, but needs to be more clinical. AFP/Getty Images

The size of a club’s fixture list is now seen as more decisive in the title race than ever with what Leicester City did, more decisive in the Champions League chase than ever with what Liverpool are doing, and with the consequences of all of that obviously having a significance for what all clubs can do in the transfer market in future.

So, what is the actual truth? How damaging should a dense fixture list actually be for a club like Manchester United? How genuinely influential is the intensity of the schedule on the league?

Jose Mourinho has made numerous complaints this season about fixture congestion (Getty)

For a start, this is nothing new or novel, making the extremity of Mourinho’s complaints all the more conspicuous. As long ago as 1967-68, John Giles was arguing about how Leeds United’s 65 games cost them winning more than the old Fairs Cup that season, and Manchester United’s current schedule would just about make the top five of heaviest Premier League schedules in the last decade [open itals] if [close] they make the Europa League final.

Team that played most games has won the title four of the last 10 seasons Average games of champions 2013-2016 big six: 51.3 Average games of champions 2009-2013 new big four: 60 Average games of champions 2004-09 big four era: 59.2 Average games of top four 2013-2016 big six: 52.25 Average games of top four 2009-2013 new big four: 55.75 Average games of top four 2004-09 big four era: 58.4

Some of those who have faced more gruelling campaigns are instructive. They are: Liverpool’s double runners-up of 2015-16 on 63; Mourinho’s own 2006-07 double-cup winning Chelsea on 64; Manchester United’s title-winning Champions League finalists of 2008-09 on 66; and - perhaps most relevantly given the profile of the squad and what they were going for - Rafa Benitez’s Europa League-winning Chelsea of 2012-13, who also had a mid-season trip to Japan.

If Mourinho’s current United are obviously not expected to win everything as in 2008-09, nor be satisfied with finishing eighth like Liverpool last season, it should not be beyond them to claim two trophies and a top-four place. Benitez did very well in this regard, as Sir Alex Ferguson even said at the time.

This is the life of a big club. As Keane argued, intense schedules are part of the deal. Mourinho of course knows this better than anyone, having guided multiple clubs through similar. In the Portuguese’s first spell at Chelsea and then through the 2004-09 ‘big four’ era that he played a huge part in solidifying, the average number of games played by all English Champions League qualifiers was 58.4. Seasons like this were par for the course.

Have United really suffered from a packed fixture schedule this season? (Getty)

That obviously means life has changed for the big clubs since then, and this is where Mourinho has something of a point. When it was just the four same clubs always qualifying for the Champions League, it helped insulate them, creating a gap between that quartet and the rest and also instilling them with the European experience that meant they regularly got to the last four. This also acted as a great equaliser in terms of amount of fixtures.

Most games of a Premier League side in last decade: 69 - Chelsea 2012-13: Europa League, World Club Cup, third place 69 - Liverpool 2015-16: Europa League final, League Cup final, eighth place 66 - Manchester United 2008-09: champions, League Cup, World Club Cup, CL final 64 - Chelsea 2006-07: FA Cup, League Cup, second place 62 - Chelsea 2007-08: second place, Champions League final 61 - Chelsea 2011-12: Champions League, FA Cup, sixth place 61 - Arsenal 2008-09: fourth place 60 - Manchester United 2010-11: champions, Champions League final 60 - Manchester United 2006-07: champions, FA Cup final

That has changed. There are now a big six rather than a big four, and a side who suddenly have more time to keep everyone fresh and perfect training-ground approaches will suddenly have a significant advantage. That is proved by how Liverpool finished second in 2013-14 after just 43 games, Leicester won the title last season after the same amount, and Chelsea are doing similar this year with what would be a maximum possible of 47. They have brought the average games for the top four in the last three years down to 52.3, a difference of more than eight from the ‘big four’ era.

At the same time, that change shouldn’t be overstated when it comes to who can win what. All three of those came from freak seasons where United had appointed David Moyes, absolutely everything fell right for Leicester, and Chelsea don’t have European football because of the chaos of last term.

They are unlikely to be repeated, and all of the big six will be in continental competition in 2017-18. Not all of the big six, however, will have the same budgets. This is just one other way that the Premier League, like with its broadcasting deal, has convolutedly come to a competitive balance.

Mourinho has experience of dealing with busy schedules but continues to voice his complaints (Getty)

The true 'wealthy four' of Manchester City, Chelsea, Manchester United and Arsenal should really have the resources - and certainly above Liverpool and Spurs - to balance a series of competitions and do well in them.

Total games of English champions since 2004-05 2015-16 Leicester City 43 2014-15 Chelsea 54 2013-14 Manchester City 57 2012-13 Manchester United 54 2011-12 Manchester City 55 2010-11 Manchester United 60 2009-10 Chelsea 56 2008-09 Manchester United 66 2007-08 Manchester United 57 2006-07 Manchester United 60 2005-06 Chelsea 54 2004-05 Chelsea 59

That, again, is life at a big club. Barcelona and Real Madrid are regularly facing those seasons, and in a league where their teams outperform everyone in the Europa League. Sevilla have played an average of 60.7 games over the past three seasons, for example, compared to Barcelona’s 60.3. Back home, Sir Alex Ferguson’s last few seasons regularly saw his sides play 60-game seasons. Even a patchier United got to the Champions League final and won the league title in 2010-11 despite that exact amount of 60. Given everything that happened that season with injuries and Wayne Rooney’s contract, they aren’t too far ahead of the current squad, one Mourinho said he was happy with back in August.

It’s also not like the good team with the least amount of fixtures is guaranteed to win the title, let alone qualify for the Champions League. City won it in the first of these more open seasons in 2013-14 despite more matches than anyone on 57. In fact, that made it four of the last 10 campaigns where the most stretched squad stole away the Premier League.

Chelsea have played the fewest number of games (35) out of the top six so far this season (Getty)

None of this is to say Mourinho doesn’t have something of a point. The science demands that players should have at least 72 hours between games, and it helps the development and devastating effect of a side if the same core squad can build deeper on-pitch relationships over a greater number of games. Chopping and changing doesn’t help that.

The point is that most of the clubs face this. All managers except Antonio Conte and Jurgen Klopp have these complaints this season, and it is one area where Mourinho and Arsene Wenger would find a lot of common ground. United have actually just played three games more than City, and six more than Arsenal and the lesser-resourced Spurs, with some of them the Community Shield and dead-rubber Europa League games.

Whether it’s right or wrong, dealing with this has become a key management skill in itself, and one Mourinho has proven himself very adept at. He does have a point, but the fixture list is not the ultimate proof of why someone wins what.