Conor McGregor says Abdulmanap Nurmagomedov will be "doing tumbles in his grave" after his nephew tested positive for a banned substance.
Usman Nurmagomedov, the younger cousin of McGregor's rival Khabib, was handed a six-month ban and fined $50,000 after testing positive for an undisclosed banned substance just days before his Bellator 300 bout with Brent Primus on October 6.
Usman defeated Primus by unanimous decision to retain Bellator's lightweight championship belt, but that result has been overturned to a no-contest following the positive test.
McGregor, who lost to Khabib in 2018 after a poisonous build-up, which led to a brawl breaking out after the fight, took to social media to take a swipe at Usman in a series of since-deleted tweets.
He said: "The shame of Allah hangs over the Nurmagomedov clan.
"Cheaters! Abdulmanap is doing tumbles in his grave."
Usman released a statement to state that the failed test was due to medication he had been prescribed by a doctor, which he did not notify the Athletic Commission about.
He wrote: "I would like to give a comment regarding the latest news on my suspension.
"The results of my test revealed a prohibited substance that entered my body through medications, prescribed to me by a doctor.
"A few months before my fight, I was undergoing treatment, but unfortunately, I did not notify the Athletic Commission in advance.
"I would like to note that the California State Athletic Commission conducted its own full investigation, where I provided all the necessary documents, doctor notes, and medical certificates, thanks to which the period of my disqualification was reduced to 6 months, instead of longer suspensions accepted in such cases."
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