Yet another manager goes with Blues having to play them in the next month!
McAllister's 11-month reign ended after Bates and fans reacted angrily to Leeds' 3-1 defeat at MK Dons on Saturday. It was their fifth successive defeat and left them five points short of the League One play-off places.
Former assistant manager Gus Poyet and former Watford chief Boothroyd are the leading contenders.
The club are expected to appoint a successor swiftly and Boothroyd is available immediately after his dismissal by Watford last month. The 37-year-old has ties with United after spending a year at Elland Road as coach during the 2004-05 season. But he has already rejected overtures from Huddersfield and is believed to have had reservations about dropping into League One after taking Watford into the Barclays Premier League two and a half years ago.
Peterborough boss Darren Fergurson has been mentioned but how the Leeds fans would react to the son of Fergie arriving at Elland Road one can only imagine, it would be an understatement to say they don't like Manchester United, but his appointment would be typical Bates!
Though any rumours linking Roy Keane or Paul Ince to the job would be a bit much for the Leeds faithful to take!
After the FA Cup humiliation at Histon last month, Bates has grown concerned the club could get stuck in football's third tier for another season and issued a statement which said: "This decision was made to ensure the new manager has the maximum number of games possible to move the club up the table. We also want whoever comes in to be able to identify any new players he feels would strengthen the squad."
A statement on the club's official website reads: "The club would like to place on record its thanks for the loyal service given to Leeds United by Gary since joining the club as manager in January 2008, and wish him every success in the future. The club will make no further comment on a replacement until we are in a position to make an appointment, which we are committed to doing as quickly as possible."
McAllister, who won the league title with the club as a player in 1992, the season before it became the Premier League, took over from Dennis Wise. He steered Leeds to the League One play-off final last May, but the team lost to Doncaster. Failure at Wembley made McAllister determined to achieve automatic promotion, but the side are 15 points behind runaway leaders Leicester, who they entertain on Boxing Day.
Leeds legend Eddie Gray felt the club should have given his fellow Scot more time to arrest the slump. He said: "It's the simplest thing to criticise the manager and lay the blame at his door, but I always had a lot of faith in Gary. He's in a tough place, there's no doubt about that. But he deserved the opportunity to fight his way through it and to show that he could cope with the pressure."
Norman Hunter, another Leeds favourite, also felt the club acted too hastily in dismissing the Scot. However, he believes that, despite the club's downward spiral since the early part of the current decade, the managerial hotseat at Elland Road remains one of the "best jobs in the country".
As a result, he expects a raft of high-rank applicants. "I'm sure there will be plenty of good candidates out there who fancy taking Leeds United at this moment. The club is well set up and I think it is an excellent job for an experienced guy who wants to step back into the game. I don't think it is a hard job. I think it is one of the best jobs in the country."
The bookies wasted little time in installing former Watford boss Boothroyd as their market leader, Victor Chandler going 3/1 while Sky Bet and William Hill both offered 4s. Poyet is top-priced 5/1 with Hills.
John Sheridan, Billy Davies, Iain Dowie and Simon Grayson are other men in the frame looking at the early prices.
Another name mentioned in dispatches is the man who was in charge of the team who saw off McAllister; Roberto Di Matteo, the manager of MK Dons. He is well known to Bates from their Chelsea days.