Abdulmanap Nurmagomedov, father and trainer of Russian UFC lightweight champion Khabib Nurmagomedov, has been refused a US visa to watch his son’s title fight with Conor McGregor in Las Vegas on October 6.

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Abdulmanap underwent an interview at the US embassy in Istanbul on Friday, but his application was not green lighted. "They denied (my visa)," the 55-year-old told TASS.

Khabib himself had ealier expressed doubt over his father’s chances of obtaining a visa in time for the much-anticipated showdown with Irishman McGregor.

“Still work but I think maybe no,” the Dagestan native answered in reply to a reporter who asked about the issue during last week’s New York City presser between the two. An earlier visa for Nurmagomedov Sr was annulled a few years ago.

In August, Khabib posted an image to Instagram in which he hinted at a resolution to the problem with a doctored photo of US president Donald Trump granting his father a visa in the White House.

Father and son enjoy a close relationship, as Khabib, undefeated in 26 professional MMA contests, constantly gives praise to his father’s training rituals in the lead up to and after fights.

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The younger Nurmagomedov is currently in the US putting the finishing touches to his training at the American Kickboxing Academy (AKA) for his mega fight with McGregor, which will headline the UFC 229 card at T-Mobile Arena.