Gurkhas are a Nepalese warrior clan known for being lethal and deftly eviscerating enemies with their Khukri (dagger).
An Old Trafford source told The Sun: "The Gurkhas have a formidable reputation. We have been told this guy was military decorated. You wouldn't want to cross him."
The security man has been provided his own living quarters at the striker's house and keeps a watch over both the player's homes in Prestbury, Cheshire.
A string of robberies at the homes of absent Premier League stars where their kin were intimidated led to the hiring of the Gurkha guard.
Victims include United's Darren Fletcher, 26, whose partner had a knife held to her throat.
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