Saturday was Keegan's first match as Chief Operating Officer at Fulham, 8,805 turned up, up on the last Craven Cottage game but not the season's best. They politely cheered a 3-1 win over moderate Oldham Athletic.
While Keegan is largely right to say all football fans are passionate about their team, there is a difference between the black-and-whites of the Toon and those of the Thames. St James' Park dominates Newcastle city centre like a medieval castle keep. Beneath it every other person wears a Newcastle shirt. It is such a deeply symbiotic relationship Sir John Hall's vision of a Geordie nation being uplifted by a giant Newcastle Sporting Club is not a fanciful one.
Craven Cottage is charming rather than imposing, supporters arrive via Bishop's Park where pensioners sit in the rose gardens and small boys play football - wearing the colours of Arsenal and Chelsea, Rangers and the inevitable Manchester United. The fans like their football, but they do not believe Keegan is a Messiah come to lead the Putney nation out of the wilderness. While success under Mohamed Al Fayed, Keegan and Ray Wilkins would naturally be welcomed, there is a wariness about the price.
David Lloyd, the editor of the long-running fanzine There's only One F in Fulham said: "Many fans are gutted with the way Micky Adams [who took Fulham up last year] was treated. Fulham fans have suffered so much for so many years under managers who've stayed past their sell-by date, then along comes a guy who gives them some success only to be tossed aside. He wore his heart on his sleeve, as Keegan does, and he had a real rapport with the fans.
"That makes us worry about how we will fare. It would be dreadful if we got in the Premiership only to find loyal fans could not afford the prices," Lloyd said.
This happened at Newcastle where the club's response was that success had a price, the best players needed funding and that genuine Newcastle fans should be happy that the team was winning. The disenfranchised were not entirely convinced and Fulham fans, many of whom have been attracted by the club's "winning isn't everything" image, are even less so. There had, admitted Lloyd, been a substantial minority who did not want to sacrifice the club's unique atmosphere. As one fanzine contributor wrote to Al Fayed in the current issue: "Please remember that football should be, always and above all else, about fun and entertainment."
The fans are not the only ones uncertain about the future. Fulham's players must be feeling extremely vulnerable. A transfer pot of pounds 10m is waiting to be spent and they have been given a month to show they have a place in the new Fulham.
Wilkins, the team manager, admitted that some players might be feeling insecure but added: "You will never play this game if you have inhibitions about your ability. You have to express yourselves and that is what we have tried to impress on the lads - feel free to play."
Their nerves were evident in the early stages, which Oldham, on a good run of form, controlled. Then Fulham's Jurgen Klinsmann look-a-like, Richard Carpenter, played a fine ball to Paul Moody, who steered it past Michael Pollitt with a touch Keegan would have been proud of.
Oldham then became, as their manager, Neil Warnock said: "abysmal". Moody added a second after Pollitt rashly charged a Steve Hayward cross, then Lee Sinnott, under pressure from Moody, put into his own net. Moody, signed for a current club record pounds 200,000 from Oxford United, will score goals in this division and should stay awhile. However, the new realities were betrayed by the body language of his partner, last season's top scorer Mike Conroy, when he was replaced by on-loan Leon McKenzie late on.
Wilkins also said: "We will introduce players when we feel the need to" and, though Fulham have the basis of a promotion-winning side, few will survive if the club progresses as planned. The Newcastle example suggests a rapid turnover is likely, with players signed to do a job then discarded.
In his early months at Newcastle, Keegan (who will be making these decisions with Wilkins), restricted by the slow release of funds and the transfer deadline, added just Brian Kilcline and Kevin Sheedy to the team as he staved off relegation. A year on, promotion was achieved by an almost- new XI, only Kevin Scott and David Kelly remaining. They soon departed and, by the time Keegan walked out, three-and-a-half seasons on, Rob Lee was the only promotion winner still a regular.
Warnock, who has won more lower division promotions than most, said: "The players will be looking over their shoulders but they have to do the business whatever club they are at. No doubt one or two of the lads he [Keegan] thinks will probably be leaving will surprise him, and he'll keep them on and others he'll let go.
"I don't think promotion is automatic this season, we have just as much chance, but I'll be very surprised if they aren't promoted next year. Heads must roll if they don't." The last comment was tongue-in-cheek but probably right, though the rolling head will be Wilkins rather than Keegan.
On prospective signings, Warnock warned: "You need quality but it has to have the right temperament for the division. Then get the team spirit going and things will take off.
"It's going to be an interesting time and it's good for Fulham fans. I can remember coming here as a teenager with Chesterfied when Johnny Haynes was here and nothing's changed. They haven't had a lot to shout about over the years, so apart from the sadness over Micky Adams, it's great for them."
Despite reservations, most Fulham fans appear to agree. As one said at the turnstile: "We better make the most of this, we won't be able to stand on the terraces in the Premiership".
Goals: Moody (10) 1-0; Moody (52) 2-0; Sinnott og (64) 3-0; Hodgson (72) 3-1.
Fulham (3-5-2): Arendse; Cullip, Blake, Lawrence; Smith, Carpenter, Cockerill, Hayward, Herrera; Moody, Conroy (McKenzie, 80). Substitutes not used: McAree, Cusack.
Oldham Athletic (4-4-2): Pollitt; McNiven (Riches, 63), Sinnott, Garnett, Serrant (Salt, 83); Orlygsson, Graham, Duxbury, Wright (Innes, 65); Barlow, Hodgson.
Referee: G Singh (Wolverhampton).
Booked: Fulham Lawrence, Cockerill. Oldham Hodgson, Orlygsson, Wright, Garnett.
Man of the match: Moody.