Continuing their adventure in the Cotswolds, the pair came across a shop that they both wanted to visit.
However, the pair clashed when Christina decided to initiate a race.
Joyfully hoping to find some bargains, she said: “Right, are we going to have to have a race into the shop?”
Slamming the car door as his rival locked up, Mark ran off and said: “There’s no competition! Bye!”
Antiques Road Trip broadcast BREAKS DOWN leaving viewers baffled
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Antiques Road Trip: Mark Stacey SLAMS door in rival Christina Trevanion’s face in danger run
Oh sorry were you behind that? I didn’t see you there!
Struggling to get out of the low vehicle, it took Christina a moment to realise that Mark was not waiting around to make it a fair race.
She gasped: “Gosh it’s very low down there isn’t it. Oi! Come back!”
Voicing the show, Tim Wonnacott said: “Hey, danger ahead! They’re sharing a shop. Oh no!”
Slamming the door in Christina’s face, Mark looked overjoyed and gave a thumbs up to the camera, as his fellow expert snapped again.
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Playing innocent, Mark replied: “Oh sorry were you behind that? I didn’t see you there!”
It comes as the pair had an auction showdown in good humour in yesterday’s episode, with Mark refusing to speak to Christina.