Macho men: Cristiano Ronaldo was so sure of his muscles that he jokingly challenged cage fighter and mixed martial artist Conor McGregor to a brawl on Tuesday

Squaring up for a fight, the musclebound duo posed with the arms outstretched, ready to throw a punch as they faced each other in the ring.

But Cristiano proved it was all fun and games as he captioned the snap: ‘Great to see you bro!!’

The feeling was mutual as Conor shared his own picture of the pair writing: ‘My brother Ronaldo dropped by the gym today! He is an animal. Thank you @cristiano, much respect! I will see you for that Forbes number 1 spot next year. #ThisIsTheMacLife.’

Fighting talk: Sharing a snap of the pair together on Instagram, the 31-year-old Portuguese footballer showed off his chiselled abs whilst Conor, 28, flexed his bulging biceps in the shirtless snap

Meet the muscle: Bumping into more muscle-clad men, Cristiano also paid a visit to Hollywood hard man Jason Statham in Beverly Hills on his 49th birthday

Clad in matching denim shorts, the pair were evenly matched in their intimating appearance as they showed off their phenomenal physiques.

Accentuating each and every muscle, Cristiano sported a deep bronzed glow, with a tan line just visible above his red briefs.

Concealing his slicked back locks, the Real Madrid mid-fielder donned a backwards white baseball cap that matched his brilliantly white trainers.

Kicking off the party: Continuing with the birthday theme, he also attended Jennifer Lopez’s 47th celebrations in Las Vegas on Saturday

Selfie time: The Ain’t Your Mama singer strode into her fête wearing a gleaming green jumpsuit before she settled down to snap pictures with the handsome Portuguese player

Bumping into more muscle-clad men, Cristiano also paid a visit to Hollywood hard man Jason Statham in Beverly Hills on his 49th birthday.

Sharing a snap of the pair, he wrote: ‘Look who I found!’

Continuing with the birthday theme, he also attended Jennifer Lopez’s 47th celebrations in Las Vegas on Saturday, where he was reunited with his friend Conor.

Leggy lady! J.Lo couldn’t resist flashing her perfect pins as she posed for snaps with Conor