The man known as the 'King of Kings' by an adoring Parkhead public is already the clear favourite to replace Neil Lennon as Celtic boss. Idolised after netting 242 goals in 315 games for the Hoops between 1997 and 2004 before departing for Barcelona, the Swede would win the instant backing of the club's huge support. Has managerial experience with Landskrona and current club Falkenberg.
The Aston Villa boss is another former Celtic player whose playing honours would win him kudos from the Celtic faithful. He skippered the team which lost the 2003 Uefa Cup Final in Seville and has gone on to build up a decent record in charge of Wycombe, Colchester and Norwich. He has faced difficulties of late in his efforts to transform Villa.
Another to have worn the Hoops, Mackay has been out of work since his spectacular fall-out - that led to his sacking - with Bluebirds owner Vincent Tan. The 42-year-old kept Watford in the Championship in his first managerial job before guiding Cardiff up to the Premier League.
Coyle's star seemed to be forever on the rise, but after taking Burnley to the Premier League, relegation with Bolton was followed by a disastrous spell with Wigan in the Championship. When he signed with the Latics, he had a release clause that would be activated if the Hooops came calling. Would welcome the chance to manage his boyhood heroes.
Yet another former Hoops player. The Dundee United boss has made an encouraging start to life as a manager since hanging up his boots three years ago and is an outside bet. Sent Partick on their way to the SPFL Premiership last season but quit for Tannadice before promotion was clinched. His young team may have lost the Scottish Cup final but they have enthralled with their free-flowing football.
A wildcard. The Spaniard left Brighton after guiding them to the play-offs where they were defeated by Derby County. Quit after frustration at lack of transfer funds, which may not go down well in the Celtic boardroom. Would be a left-field choice, but a commitment to attacking football should win over fans at Parkhead.