Assistant managers can fade into the background. They are the men cut out of the close-up and ignored in song, rarely eulogised or vilified. Ultimate accountability lies elsewhere. And yet Manchester's footballing community has recently received a reminder of the impact they can have.
The death of Malcolm Allison, half of Manchester City's greatest management team, brought a deluge of tributes. Along with Brian Clough's invaluable ally, Peter Taylor, Allison ranks among English football's greatest sidekicks. But so, arguably, does a more recent second-in-command to grace the city's dugouts.
And perhaps the recent outbreak of nostalgia among his rivals will prompt Sir Alex Ferguson to revisit his own history. As the ongoing excellence of Ryan Giggs and Paul Scholes illustrates, Ferguson has looked to the past for renewal before and, following his sacking by Portugal, Carlos Queiroz is available again. Like Allison and Taylor, he appears doomed to be deemed a far greater coach than manager, but Ferguson's esteem for his old ally remains high.
The Scot served as a character witness for his former assistant when Queiroz was accused of disrupting an anti-doping test. He is serving a six-month suspension in his homeland, but, while it represents a black mark on his CV, that would not preclude him from working in England.
Moreover, should his two previous spells at Old Trafford provide an accurate guide, there are reasons to believe that he could provide a rather cheaper tonic than some of the many mooted transfer targets. As the move for Bebe shows, Ferguson has continued to tap into Queiroz's knowledge of the Portuguese and Brazilian markets.
While his judgment is not impeccable, as those who remember Manucho's inglorious spell at Old Trafford can testify, his advice has brought two notable coups: Cristiano Ronaldo, United's outstanding signing of the last decade and a man who produced a £68 million profit, and Nani, who is starting to deliver the blend of fancy-footed flair and fine finishing that became his compatriot's hallmark.
It is a sign that Ferguson heeds Queiroz's counsel. Mike Phelan and Rene Meulenstein, his current subordinates, are not men of the same stature and, given the pedigree of some of the 68-year-old's other adjutants - Walter Smith, Steve McClaren, Brian Kidd and Archie Knox - it is hard not to view the current crop as their inferiors.
Bouncing ideas off a former Real Madrid manager, who has led three different national teams, is a more attractive option than sharing them with a coach who comes across as a serial yes-man. Given Ferguson's enormous achievements and tradition of intimidation, does Phelan have the credibility to question his decisions?
In contrast, Ferguson and Queiroz were even described as co-managers, though it is hard to imagine the former sharing top billing with anyone. That United's sometimes erratic squad rotation tended to operate rather more smoothly during Queiroz's four-year second spell at Old Trafford is an indication that some of the stranger ideas were never implemented.
Queiroz may not have the same incendiary willpower that Ferguson possesses - few do - but there are indications they complemented one another well. The Portuguese has the linguistic skills to communicate with those who find Glaswegian an unintelligible dialect. He is also more of a hands-on coach than Ferguson and, as a tactician, is credited with persuading the older man that United required an evolution from their traditional 4-4-2 to a three-man central midfield to triumph in Europe. It rendered the 2008 Champions League victory possible (even if the final was a match United began by reverting to 4-4-2).
A further appeal for a club who have been uncharacteristically ragged at the back this season is a reputation as a defensive strategist. The partnership of Rio Ferdinand and Nemanja Vidic was united and drilled in his time in Manchester and his final season coincided with the best defensive record in the club's history, when a mere 22 goals were conceded.
While his time with his homeland included one or two embarrassing displays - notably the 6-2 defeat to Brazil - they were separated by a run of 26 games that included 22 clean sheets. Portugal's may well have been the best defence in the World Cup and a cash-conscious club should be aware it is often cheaper to construct the most resilient rearguard than the most potent attack.
So, with Ferdinand's body creaking and Edwin van der Sar's career (logically) in its final furlong, it could be an apposite time to enlist a coach who could fashion a new-look defence. Because while Queiroz's influence appeared to irritate Roy Keane, among others, in the traumatic autumn of 2005, the consensus is that it was hugely beneficial.
And now, in the wake of the reassurances about the club's ambition that Wayne Rooney has received and the supposedly sizeable budget Ferguson has at his disposal, speculation rages about supposed signings next summer. Another superstar would be a welcome addition, yet the most significant could be reuniting Ferguson with his favoured right-hand man.