Talent alone is not enough. That has long been the attitude at Old Trafford. It is not that Manchester United teams lack ability - that is an accusation that can rarely be levelled - but that the ingredients for success go far beyond that.
The quintessential United players of the last quarter of a century have shared Sir Alex Ferguson's will to win. Outlining the qualities of some of his great players, the Scot once listed: "In addition to skills, physical strength, courage, toughness of mind, speed, power and determination." And, whether as flamboyant as Cristiano Ronaldo or as unflashy as Brian McClair, he could have noted that they possessed a versatility and a resourcefulness that their rivals can only envy.
And now it is being tested as it rarely has been before. The injuries that have sidelined up to 15 players have made new demands on the last men standing. Thus far, they have responded admirably. Today they face Aston Villa, whose blend of pace, power and set-piece expertise will invariably present problems, but Ferguson's charges are becoming accustomed to changes in their job descriptions. Unyielding characters are proving adaptable players.
Following a slow start to the season, Michael Carrick was starting to reassert himself in the centre of the pitch before becoming an ersatz centre-back while Darren Fletcher's development from fringe player to one of the Premier League's finest midfielders was no sooner completed than he had to acclimatise to life in defence. "Tactics do not win football matches," Ferguson has said. "Men win football matches."
This has been a week to justify that statement with Carrick and Fletcher among a back three who prospered in Wolfsburg in the Champions League on Tuesday. Nemanja Vidic should return from flu today, giving United a specialist centre-back. But one man who will not be playing that position in the new year is the former England international Sol Campbell. "Campbell was a great player, but he is not a player we are thinking about getting to come to United," said Ferguson yesterday, following much speculation that the 35-year-old defender would be on his way to Old Trafford next month.
Alongside Vidic today, the likelihood is that either Carrick or Fletcher, and probably both, will still have defensive duties. A Villa midfield featuring three wingers provides a different challenge of a makeshift full-back such as Fletcher, who is likely to mark Stewart Downing. After the aerial test in Germany, Villa offer more of an examination of acceleration. If a duel between Ashley Young and Patrice Evra could be an even contest, a race between Carrick and Gabriel Agbonlahor threatens to be rather more one-sided.
The latter struck at Old Trafford last season when a laudable draw was turned into a dramatic defeat by the injury-time intervention of United debutant Federico Macheda. With Ryan Giggs, Wayne Rooney and Dimitar Berbatov back again, the Italian teenager is unlikely to be required today. It will be more intriguing if Michael Owen, fresh from his hat-trick in Wolfsburg, is selected. Whichever, the encounter is a barometer of Villa's progress.
They have ambitions to break into the top four and defeated the league leaders, Chelsea, but rarely overcome the dominant side of the current era. United are unbeaten in 24 matches, winning 21 of them. Villa's last league victory came in the opening game of the 1995/96 season, prompting pundit Alan Hansen's infamously incorrect statement that "you'll never win anything with kids", while they have not won at Old Trafford since 1983.
The team from the Second City have invariably come off second best. "Our defensive record is quite good," said Martin O'Neill. "But you could go in with the best defensive record and still come out well beaten." That is the experience of United's recent opponents. It is one of the features of the season that while the major clubs stockpile players, injury crises appear more frequent. But peeling off four successive wins, United have acquitted themselves better than at times when there were rather more options available to Ferguson.
Opportunities have been provided and taken. Darron Gibson, who has started the last three games, said: "I don't like players being injured but it has given me a chance. Hopefully they keep coming." But there are precedents at Old Trafford. Many of United's triumphs have been notable for players' versatility. It is possible to remember Mark Hughes operating in midfield and Roy Keane at right-back when their 10 men defeated Charlton in the FA Cup in 1994, or David Beckham and Giggs adopting unfamiliar positions in the Champions League final five years later.
There was Phil Neville's mid- career move from jobbing full-back to tireless midfielder, beginning with the defeat of Arsenal in December 2002, and the unexpected discovery that Ole Gunnar Solskjaer, their professional predator, could prove to be a terrific right winger. Necessity has been the mother of reinvention for Manchester United before. It seems to be so again. firstname.lastname@example.org
Manchester United v Aston Villa, 9.30pm, Showsport 1 & 2