Conor McGregor sent Ryan Garcia a chilling threat and told the troubled boxer to 'get your head together or kill yourself' after he tested positive for a banned substance.

Garcia failed anti-doping tests the day before and the day of his upset win over Devin Haney last month. The 25-year-old - who also came in 3lbs overweight - tested positive for the performance enhancing ostarine but the results did not emerge until after the fight.

He has denied cheating but McGregor sent Garcia an X-rated message on social media, warning that if he was Haney's dad 'you're dead no matter what.'

'GET YOUR HEAD TOGETHER OR KILL YOURSELF,' McGregor wrote before the post was deleted.

'Cheated the weight and was juiced, lifetime ban. Sad to see, sad to say. Sad and a bit sick. Don't come near me if I ever see you again Ryan Garcia.

'I am actually disgusted... If I was Haney's dad you're dead no matter what for doing that. Crazy. What the f*** happened to you, you little fool.

'Get your head together (because) I'm gonna smash it in with elbows if you don't. Fair play Devin well done. Your performance has just become even more heroic.'

McGregor, who is slated to return to the UFC next month after three years out, also took aim at fellow UFC fighter Sean O'Malley.

O'Malley tested positive for ostarine in 2019 and McGregor offered to fly both him and Garcia to Dublin for a scrap in the parking lot.

'I'll bust yous both up, do yous want a spar I will set flights right now for you both for a full on spar each. Hotel, black forge inn the lot,' he wrote.

'I'll ride you both like yous are ostriches. WTF is up. What do you think are at?' 

After the results emerged, Garcia insisted: 'Everybody knows that I don't cheat... I've never taken a steroid.'

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