The Rangers assistant supervisor and former Leeds United captain were outdoors a bar in Call Lane while he turned into attacked at approximately 04:00 GMT on Saturday.
He became reportedly punched inside the face and required medical institution treatment and is convalescing at domestic.
Former Leeds player Dominic Matteo said the assault left McAllister without three-tooth and wanting plastic surgical treatment and stitches in a Facebook publish.
West Yorkshire Police has no longer named McAllister but showed officers were investigating an alleged attack.
Unprovoked and harsh
McAllister, Steven Gerrard’s assistant at Rangers, is said to be recuperating at home in North Yorkshire, in line with The Sun newspaper.
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The fifty-four-yr-vintage has been out for a meal inside the town centre along with his spouse after they were attacked even as looking ahead to a taxi, the newspaper stated.
In the Facebook publish, Matteo defined the assault as “totally unprovoked and really vicious.”
He introduced: “The attacker is an idea to be American, and due to the severity of the injuries may also have been carrying a ‘knuckle duster’ or similar.”
McAllister won 57 caps for Scotland and captained the crew to the Euro ’96 finals.
He played for Leeds from 1990 to 1996, during which period they became champions of the previous First Division in 1992.
He additionally captained the crew for two seasons before transferring to Coventry City.
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The former midfielder joined the management team at Coventry in 2002, after playing for Liverpool, and took up his position at Rangers remaining yr.
Det Insp James Entwistle, of Leeds District CID, stated: “The initial file turned into that a person, elderly in his 50s, was stood out of doors a bar whilst a person approached him and punched him in the face causing accidents that required sanatorium treatment.
“We are presently arranging to talk to the victim to take fuller information of the incident and maybe progressing the investigation to pick out the individual responsible.”