Atletico are determined to keep hold of Trippier - but have drawn up a two-man transfer shortlist should United sign him, says the Mirror.
The England international has been the source of constant speculation after it emerged he was a target for Ole Gunnar Solskjaer.
They are said to be holding out for £30million for Trippier - some £15m more than United had hoped to snag him for.
Santiago Arias and Sime Vrsaljko are both internal candidates to fill the right-back berth, while Nelson Semedo (Wolves) and Giovanni Di Lorenzo (Napoli) are on their radar to bring in as replacements.
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