And now the Irish cutie - who's just finished touring America, Australia and New Zealand with the 1D boys - has been poking fun at Olly Murs after he told his Twitter followers he was squaring-up for a boxing match against his personal trainer.
'Sparring with @1georgiekean today down in EAST LONDON!! Gloves are on... Fancy my chances... Lol,' wrote Olly, 27, yesterday.
Of course naughty Niall, 18, couldn't resist making a jokey comment.
'@ollyofficial olly you wouldnt knock snow off a rope! hahahaha,' he quipped before adding, 'i'll take ya on!'
Who do you reckon would win? Our money's on Niall...
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