Sam Heughan's Outlander co-star pokes fun at him for hilarious reason

The actor left fans in stitches…

Sam Heughan and his Outlander co-star Steven Cree clearly have a great bond. The actors, who appear together as Jamie Fraser and Ian Murray in the Starz show respectively, often poke fun at each other – particularly on social media – and Sam's recent snap on Instagram invited a very cheeky comment from his fellow thespian.

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On Sunday, Sam uploaded a snap of himself shirtless in sunny Mexico while enjoying some exercise, writing in the caption: "Managed to squeeze in a workout, at the end of my trip to Mexico… IN THE JUNGLE!?"

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WATCH: Outlander's Caitríona can't resist making fun of Sam Heughan in latest video

Despite the snap sparking a major reaction from fans, who were commenting on his impressive level of fitness and muscular physique, Steven hilariously wrote: "Could you breath in anymore son??", before adding sincerely: "Looking good."

Many of Sam's followers responded to the actor's light-hearted comment with a number of laughing-face emojis. One person wrote: "@thestevencree He's like... hurry up!! Take the pic... take the pic!! Just kidding... Sam's looking [fire emoji]."

Another commented: "@thestevencree yes I was wondering … cuz [sic] he didn't look exactly like that with the model by the pool. So do you just breathe in then for a photo?? Good tip! You look crazy great Sam… just messing with your perfection."

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Sam shared this photo on his Instagram recently

A third said of Sam's photo: "Yes. I don't know what I'm saying yes to, but the answer is yes."

And it's not just Steven that Sam clearly enjoys banter with. Leading actress Caitríona Balfe couldn't resist teasing her on-screen husband recently when they filmed a fan video together.

The two were admiring some art sent in by loyal fans of the drama series, when the actress, who plays Claire Fraser on the show, said of one drawing of Sam: "It's got your eyebrow thingy that you do."

Sam, looking puzzled at first, asked: "Who do I do?" which prompted Caitríona to do an impression of his signature eyebrow hook as she teased: "It's one of your five acting things." Sam then saw the funny side, adding: "I look a little confused or something!" 

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