The character doesn't appear to be named in the script, but according to the Huffington Post Beckham is "listed in the cast as playing 'Trigger'". He plays a soldier who speaks two lines, sarcastically directing the young Arthur's attempt to pull the sword Excalibur from the stone.
This is Beckham's second film appearance, both being courtesy of his close friend Guy Ritchie. The first was in The Man from U.N.C.L.E. (2015), when he played a film projectionist but didn't have any lines.
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