Temple of Oops

At a Modern PPTQ you are the Head Judge of, Ashton is playing against Naomi. Ashton plays his land for turn, a Temple of Abandon. Ashton picks up the top card of his library, looks at it, sets it back down on the table. Ashton thinks, and then picks up the card and puts it into his hand. Naomi immediately calls for a judge. What do you do?
 [expand title=”Answer”]This is a Hidden Card Error, Ashton receives a Warning. Ashton has put a card into his hand when he wasn’t supposed to, and we can’t fix it with publicly known information. Ashton reveals his hand, and Naomi chooses a card from it, since Ashton knew what the card was before he put it into his hand, we return it to the top of Ashton’s library instead of shuffling it away.[/expand]
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