The 27-year-old USA international goalkeeper will leave New England Revolution for the Gunners on July 1.
He played his final game for the Revs on Sunday and quickly demonstrated his loyalty to his new home.
Turner went over to a section of fans to sign things after the match but there was one item he simply refused to.
'Oh no', he said, as a man wearing a Spurs shirt held out another for him to sign.
He proceeded to back out of signing the top and say 'disgusting' before continuing to accommodate the other supporters.