The Rangers assistant supervisor and former Leeds United captain were outdoors at a bar in Call Lane when he turned attacked at approximately 04:00 GMT on Saturday.
He reportedly punched inside the face and required medical institution treatment and is convalescing at home.
Former Leeds player Dominic Matteo said the assault left McAllister without three-tooth and wanting plastic surgical treatment and stitches in a Facebook publication.
West Yorkshire Police no longer named McAllister but showed that 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 had been out for a meal inside the town center along with his spouse after they were attacked even as looking ahead to a taxi, the newspaper stated.
In the Facebook publication, Matteo defined the assault as “totally unprovoked and 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 they became champions of the previous First Division in 1992.
He additionally captained the crew for two seasons before transferring to Coventry City.
Scotland’s papers: McAllister battered through Yob
20 Years of Regret from Euro’s Ninety-six LossRangers’ activity persuaded McAllister to return to soccer under Steven Gerrard. The former midfielder, who had played for Liverpool, joined the management team at Coventry in 2002 and took up his position at Rangers the following year.
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 while a person approached him and punched him in the face causing accidents that required sanatorium treatment.
“We are arranging to talk to the victim to get fuller information about the incident and maybe progress the investigation to pick out the individual responsible.”