When Conor McGregor named Kieran Tierney as his favourite footballer at a press conference in Russia in October, it was just another example of the pair's rapport.
While on the face of it an unlikely sporting friendship, UFC fighter McGregor formed a bond with Tierney while our left-back was playing for former club Celtic.
Tierney admits that he's a massive fan of the Irish mixed martial artist – and is sure to be tuning in when he makes his return at UFC246 on Saturday.
"I met him in Belfast at a UFC event and that's what started it off," Tierney told Arsenal Player.
"I am the biggest fanboy of Conor McGregor ever! Honestly, the documentaries I've watched... I've watched every video on YouTube, twice!
"For me to have a relationship with him [is great].
"I messaged him back and forth on Instagram, and sent him over a shirt that he wore and put on Instagram. To see that... I didn't get any sleep that night after I saw it!
"He supports me as well, so I'm delighted to just be friends with him."
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