Their acclimatisation has been confirmed not by a League table that today proclaims Paul Jewell's team as the second finest in the land, nor by the sight of a sun-kissed Tony Jacklin swapping his home in America for a day out at a JJB Stadium made more inviting than usual by Latics Ladies Day, a promotion that resulted in genuine fears for the safety of Arjan de Zeeuw when he stepped into a sponsor's lounge to collect his "Dish of the Day" award after the game.
The proof that Wigan are a club without fear, without the inferiority complex that has afflicted so many promoted teams in the past, can be traced to a couple of seats behind the manager's dug-out where, incredibly, a few supporters bemoaned the failure to break down luckless Fulham until Pascal Chimbonda secured a fifth Premiership victory in succession in the 92nd minute.
Their complaints were too close and loud for Jewell to ignore, and though he preferred to gloss over the issue afterwards, the moment underlined how expectations are soaring at Wigan. "The fans were having a bit of a go so I just turned around and said get behind the team," he insisted. "They were only frustrated but some of them need to take a reality check. You are never surprised in this league - I guess that is the price of being in the Premiership."
Such complaints are also back-handed compliments for Jewell, who at the start of this campaign would have been deemed a success just for repeating his feat of saving Bradford City on the last day of the 1999-2000 season. Now, like Sir Alex Ferguson and Rafael Benitez, he has the task of meeting exacting demands.
Wigan's ambitious manager, surely destined to retain his Manager of the Month award for a 100 per cent record in October, will not protest too vehemently at the shifting goalposts; he is, after all, just as keen to demolish any patronising assessment of his club and players as to realise the vision of his chairman, Dave Whelan, and establish Athletic among the élite.
"People talk about that 'us against the world' spirit," added Jewell. "But we don't want to be underdogs. I don't want to be an underdog all my life. I want to be manager of a team that has a chance of winning something. I am enjoying my time at Wigan - we are all loving it. We all want to be the best we can be. Nobody gave us a chance of getting into this league and people gave us even less chance of getting anything once we were here. But we haven't adjusted our sights. In a way, this game hid a multitude of sins. But we have got seven wins - they can't all be lucky."
Luck had a role in Wigan's latest success, though with "a scratch team and a scratch system", according to their manager, it was luck they merited, having overcome a torrid start to control the second half. That they remained on level terms owed as much to the referee, Andre Marriner, as Fulham's profligacy in front of goal, with the match official guilty of several major errors, including a failure to dismiss the home keeper John Filan for a handball outside his area in the 36th minute. Chris Coleman was understandably irate. "I can understand a referee getting one major decision wrong, but three or four? Ridiculous."
Fulham's finishing contributed to Coleman's misery, however, and they were punished in the final seconds when Chimbonda climbed above the man mountain that is Papa Bouba Diop and headed Graham Kavanagh's free-kick beyond Tony Warner. The smallest team Jewell has ever fielded had taken Wigan to their highest peak, the winner a fitting metaphor for a club muscling their way into the Premiership.
The French full-back left the field dancing to the conga dirge that has been adapted in his honour.
"Wigan is the only place the song has been played - the English are mad and I love it," he said. "I have bought a flat and settled in well. But I cannot stand the pies. I hate English food."
As Jewell discovered, acclimatisation is not without complaint.
Goal: Chimbonda 90 (1-0).
Wigan Athletic (4-4-1-1): Filan; Chimbonda, Henchoz, De Zeeuw, Baines (McMillan, 74); Taylor, Francis, Kavanagh, Mahon (Johansson, 62); Bullard (Teale, 84); Camara. Substitutes not used: Pollitt, Jackson.
Fulham (4-1-4-1): Warner; Volz, Goma, Bocanegra (Rosenior, 90), N.Jensen; Diop; Malbranque, C Jensen (Elrich, 82), Boa Morte, Radzinski; John (McBride, 82). Substitutes not used: Batista, Helguson.
Referee: A Marriner (West Midlands).
Booked: Wigan Kavanagh; Fulham Volz.
Man of the match: Kavanagh.