The 41-year-old choirmaster was watching King’s College London a cappella group All The King’s Men when the show took a strange turn.
Straddling the judges' desk during the song, Bebe Rexha went wild, but Gareth was not impressed by the move.
As the song ended and the group still had their shoes on the desk, he shouted: "Get off my desk. Get away!"
Leaning under the table, Gareth soon returned with a cloth and began to scrub down the desk where the group had put their feet.Related articles
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Get off my