Even before Keegan's departure was resolved, one month short of the fifth anniversary of his unexpected return to the St James' Park stage where his playing days ended, it seems Newcastle had explored the possibility of lining up Dalglish as his successor. The man who led Blackburn to the Premiership title in 1995 and Liverpool to three championships of the old First Division has been top of their list since Keegan offered to resign after Newcastle's Boxing Day defeat at Blackburn.
Keegan was persuaded to stay, as he had been when he offered to resign at the end of Newcastle's failed Premiership title quest last season. With his long-term commitment in doubt, however, the Newcastle board started to make contingency plans they will now be obliged to put into immediate effect.
Keegan subsequently asked to be released at the end of the season, but it was agreed on Tuesday night that the parting of the ways should take effect from yesterday morning. The Newcastle directors, it is understood, had already sounded out Dalglish about taking over in the summer.
Dalglish, who recently accepted a non-contract job working for David Murray, the Rangers chairman, is believed to be keen to tackle another major management challenge and, with a Stock Exchange flotation planned in the next few weeks, the Newcastle board will be anxious to make a swift appointment. It would, though, be a supreme irony if Keegan's replacement were not just the man who filled his boots as a player at Liverpool in 1977 but someone who ultimately rejected the pressures of management at Liverpool and Blackburn.
After his less-than-happy parting of the ways with Blackburn, Dalglish may feel the desire to prove himself. Europe remains an unconquered management challenge for him and Newcastle, even in the short term, can offer him a crack at the Uefa Cup.
Keegan's assistant, Terry McDermott, and his chief scout and coach, Arthur Cox, who brought him to Newcastle as a player in 1982, have been placed in temporary charge of team affairs at St James' Park.
Dalglish played alongside McDermott and Newcastle's defensive coach, Mark Lawrenson, at Liverpool. He also had two of Keegan's major signings, Alan Shearer and David Batty, under his managerial wing at Ewood Park.
Dalglish, who was attending a funeral in Glasgow yesterday, was immediately installed as the bookmakers' favourite. Were he to resist the temptation, however, the Newcastle board might consider adopting a Continental-style managerial structure, with Bobby Robson as general manager and Peter Beardsley and Chris Waddle as coaches.
Other obviously attractive alternative targets would be Louis van Gaal, who leaves Ajax at the end of the season, and Robson's predecessor at Barcelona, Johan Cruyff. Brian Little, born in Newcastle and a boyhood follower of the club, could emerge as another strong contender, though Aston Villa instantly declared their manager untouchable yesterday.
Newcastle's chairman Sir John Hall, who is on holiday in Spain, said the club now needed time to plan their next move. "It has all happened rather quickly, but the club has to go on and Kevin would want that," he added.
The reasons behind Keegan's departure, having guided Newcastle from the relegation zone in the old Second Division to fourth in the current Premiership table, remained unclear last night. Chief among them, however, was the frustration of failing to win a major trophy. His outburst against Alex Ferguson in April, in a post-match television interview, showed how deeply his side's failing championship challenge last season was hurting.
Turning a 12-point lead into a five-point failure was the crushing blow which prompted Keegan's offer to resign on the eve of Newcastle's final match last season and the recent run of seven League games without a win clearly undermined his confidence that the current campaign might end the club's long wait for major honours.
The pounds 15m acquisition of Alan Shearer last summer took Keegan's spending to the pounds 60m mark and his thwarted attempt to sign Georgi Kinkladze last week may have been another contributory factor. It is understood that he was told by the Newcastle board to sell players first when Manchester City turned down the offer of Lee Clark plus pounds 250,000 and demanded a cash- only deal.
In the press release Newcastle released yesterday morning, Keegan was quoted as saying: "It was my decision and my decision alone to resign. I offered my resignation at the end of last season but was persuaded by the board to stay. I feel that I have taken the club as far as I can and that it would be in the best interests of all concerned if I resigned now. I wish the club and everyone concerned with it the very best for the future."
Douglas Hall, son of Sir John and a club director, added: "Kevin took over at the helm of a football club destined for relegation to the Second Division and scaled the heights of the Premier League with a style of football never before seen at St James' Park. Kevin leaves the club in a far stronger position than when he arrived and the squad of players he built up is one of the best in Europe. We wish Kevin well in the future."
McDermott, speaking at a hastily arranged press conference at St James' Park, said: "Obviously I'm saddened and I'm still shocked, but Kevin wanted Arthur and myself to carry on. He said: 'Go and give those fans what they deserve - a trophy.' If we win one, we'll dedicate it to Kevin Keegan for what he's done for the club and the area."
Hero of our Toon, page 22