But, for all of the alliterative headlines bookending his surname with ‘failure’ or ‘flop’ since his 32.4 million euro deadline day move from Everton, there remains a United coaching team which is delighted with the Belgian, whom the coaches privately describe as a model professional and excellent trainer.
"Marouane has knuckled down and acted professionally from day one," a Carrington source told Goal. "He has delivered what the manager expects from all his players: 100 percent commitment."
This is no Bebe situation, when first-team coaches took to warning their colleagues to duck whenever the 8.8 million euro signing got the ball in his first week of training.
Yet that, in turn, begs the question as to why he has become an anathema for such large groups of fans only months into his Old Trafford career. The answer, in short, is that Fellaini is not close to being worth the money the champion paid for him. That the Belgian ended up costing 4.1 million euros more than the 28.3 million euro fee agreed with Everton on the very same day the club signed him rather neatly sums up the mess created by United.
A mess is how you would describe United's entire transfer strategy last summer. A scattergun approach without any bullets. Fellaini has become the unfortunate collateral of a two-month muddle built on poor planning, risk and subsequent panic.
Andy Cole, who joined United in 1995 as the most expensive British transfer of all time, sympathizes with the Belgian and the weight of expectation that comes at Old Trafford.
"I think he's found it difficult going to Manchester United, especially for the price," Cole told Goal. "He has been in and out of the team recently and the fans have been on his back a little bit.
|THE ONES THAT GOT AWAY
How Fellaini compares ...
Avg no. of passes: 53.3
Pass success rate: 86.2%
Avg no. of passes: 54.2
Pass success rate: 88.5%
Avg no. of passes: 40.4
Pass success rate: 80.2%
Avg no. of passes: 77
Pass success rate: 90.2%
"The fans expect value for money, they expect you to perform and if you go through a bit of a bad patch and they're not sure about you, they let you know. I think it has been tough on him at the moment, but hopefully he'll turn it around.
"He has got to say to himself: 'I need to prove these people wrong and show that I'm a Manchester United player'."
Yet even if all hope is not lost on Fellaini from those in and around the club, the inquest from the fans as to how he became the fourth most expensive player in United's history continues. So what happened and, more importantly, why?
Almost three months before Ferguson announced his intention to retire on May 8, his closest ally on the club's board and arguably in the entire organization, David Gill, revealed that he would step down as chief executive in June. His responsibilities - note not the role itself - were to be assumed by Ed Woodward, who has since opted to work from the club's Mayfair office, rather than Manchester like his predecessor.
Gill, a shrewd operator in the transfer market, was handing over the reins to a man with no experience in the peculiar world of buying and selling football players. The club statement read as follows: "From 1 July, Ed will have overall responsibility for the club, including, in conjunction with Sir Alex Ferguson, facilitating transfer activity."
Close, but not quite. By July 1, Ferguson was gone, Moyes was posing for photographs on his first day at Carrington and the pair had two months until the transfer window closed.
Fellaini, Leighton Baines and Thiago Alcantara were all targets and were each subject to serious approaches from United, despite the latter's protestations to the contrary.
Things started going awry when Thiago, whose father Mazinho had made clear to United officials that his son would be interested in a move to Old Trafford, had his head turned by Pep Guardiola. He chose Munich over Manchester.
Moyes and Woodward, still keen to recruit a player of similar style, turned their attentions to Cesc Fabregas. Privately, the pair were confident that Fabregas, coming off the back of a somewhat underwhelming start to life at Barcelona, could be pulled from Catalunya.
He couldn't. United, embarrassed, with Woodward having left the Australian leg of the club's preseason global tour on "urgent transfer business" (what business?) looked elsewhere.
So onto the third diminutive Spanish midfielder who United tried and failed to sign this summer: Ander Herrera of Athletic. Again, the club got close. Again, the club thought it had cracked the code but, again, it wasn't to be. United wasn't willing to spend the 36 million euros required to trigger the 24-year-old's release clause on the final day of the window and farce reigned as a delegation of third-party advisers arrived at La Liga's HQ in Madrid to tie up a deal that simply wasn't happening.
While all of the above was going on, Fellaini, Baines and Everton were waiting. The Belgian, knowing of United's interest, had indicated to both new manager Roberto Martinez and chairman Bill Kenwright that he wanted to leave. He didn't submit a formal transfer request until the evening of deadline day at the Toffees' Finch Farm training complex in Halewood. Baines never forced the issue.
Relations between the two clubs were by this point strained and remain so to this day. Even after the transfer of Wayne Rooney from Goodison Park to Old Trafford in 2004, Kenwright, Moyes, Gill and Ferguson maintained a public and private mutual respect. However, a 33 million euros bid for both Fellaini and Baines in mid-August, shortly after the midfielder's 28.3 million euro release clause had expired, was described as "derisory" and "insulting" by the Everton chairman, soured talks. United, Kenwright felt, was trying to pull a fast one.
Running parallel to this was Everton's pursuit of James McCarthy from Wigan, which was to prove pivotal throughout a hectic deadline day at each end of the East Lancs Road.
Dave Whelan, the Wigan chairman, had held out until the afternoon to accept a 15.3 million euro offer from the Toffees for the Republic of Ireland midfielder, which effectively opened the exit door for Fellaini but with little time afforded for a deal to be done. An informal agreement over a 28.3 million euro fee was met on the morning of deadline day on the condition that McCarthy could be signed as a replacement for around 11.8 million euros. When Wigan played hardball and pushed up its asking price, Kenwright wanted to make sure that it was United which effectively paid. The ace hand was Everton's.
Then the reality of the situation hit home at United. All of a sudden, the two months Moyes and Woodward had back on July 1 had become two hours. The sum total of United's incoming transfer activity for summer 2013 amounted to the arrival of Guillermo Varela from Penarol. The 20-year-old, to date, has played 23 minutes of professional football.
The fact was and still is that the club's new order had to send a statement - any statement - both for themselves and their already unpopular bosses, with a big-money signing.
And so, in the closing hours of his first transfer window as manager of the biggest club in the UK, Moyes paid Everton 4.1 million euros more than not only the release clause that he himself had included in Fellaini's contract at Goodison Park, but also way above the price agreed only hours earlier, before Wigan and McCarthy moved the goalposts. The deal looked like an expensive gamble then and so far it has failed miserably.