Arsenal and Manchester City are the big horses and Chelsea the little horse in the Premier League race, but with Manchester United limping along in seventh position, have they backed the wrong horse in David Moyes?
Or, more pertinently, did Sir Alex Ferguson stumble into his biggest misjudgment since Rock of Gibraltar when urging United's American owners, the Glazer family, to disregard the qualities of Mourinho in order to hand Moyes the job of succeeding him at Old Trafford?
It only requires a glance at the Premier League table to suggest the experiment has gone terribly wrong.
With Mourinho's Chelsea sitting at the top of the table and improving game by game, it would not be beyond the Portuguese to aim his barbs with a subtle reminder to Ferguson and the Glazers that, when you want to back a winner, a proven ability to last the course and distance is the primary criterion.
Moyes is a good man and a proven manager in the Premier League following 11 years at Everton, but he has offered little evidence he is the man for Manchester United.
He must deliver something, somehow, in the final 13 league games of the season to show that next season really will be better.
The Glazers and Ed Woodward, United's executive vice-chairman, have given no indication of being jolted by the alarm bells that are ringing at Old Trafford and it would be wholly unexpected - and wrong - if Moyes were dispensed with now.
Patience and playing the long game remains the position, but nobody should fall into the trap of second-guessing the Glazers.
United has always been a financial investment, first and foremost, for the Americans and failure is never good for business.
With United nine points adrift of fourth-placed Liverpool following Sunday's 2-2 draw at home to Fulham, it is impossible to argue against the perception that things are getting worse, rather than better, at Old Trafford.
Under Moyes, United are 21 points worse off than at the same stage last season and, regardless of injuries, poor form, bad luck and whatever else may be cited as mitigation, it is inexcusable for a team of such talents and track record to be plumbing the depths of seventh position.
Moyes was indisputably dealt a poor hand by Ferguson when he took charge at Old Trafford last July and there can be no hiding from the reality that many of the squad he inherited were too old, injury-prone or simply not good enough.
But the same squad won the league by 11 points and that is the biggest stick with which Moyes is being beaten right now.
One manager - Ferguson - was able to motivate the squad to perform beyond their capabilities, but the other - Moyes - is having the opposite effect, with United's players failing to deliver for him.
Those players must look at themselves in the mirror, but when a manager talks about the buck stopping with him it is because he knows his job is to motivate, organise and deliver.
Moyes is not doing that and by decrying his players as "mentally soft" following the Fulham game, he is inadvertently pointing the finger at himself, the man charged with ensuring his team have the confidence and belief to perform.
Just as concerning for Moyes is that there is no visible pattern to his team's play beyond, as Rene Meulensteen suggested on Sunday, "get it wide, get it in". As for a philosophy or vision for the future, it is shrouded in a fog of confusion.
When Liverpool toiled away under Brendan Rodgers last season and failed to qualify for Europe, the manager earned time and support because there was a clear sense of the team developing and growing.
Liverpool's players bought into the Rodgers ethos, but if Moyes is attempting to get a message across at United, his players are either not listening or not taking it on.
Perhaps that is the root of Moyes's problem. Big-time players, those who have won titles and cups, know how to win, but Moyes walks into the United dressing room daily with a CV bereft of the kind of success his squad once took for granted.
How does Moyes persuade those players that his way is the right way, when he has nothing to show for it beyond cuttings of league tables with Everton just outside the top four?
At Chelsea, there is no such credibility gap with Mourinho and that is a major factor in their success so far this season and the coach's ability to turn a team who were going nowhere into title challengers.
Moyes, for all his efforts, is achieving the opposite at Old Trafford, with United performing the biggest and most dramatic collapse since Devon Loch.