A Bola says United are close to agreeing a fee with Benfica for the Argentina international.
United have been chasing Gaitan for some time now and according to the reports in A Bola the club are keen to secure his signature as quickly as possible.
New United boss Louis van Gaal is reportedly a big fan of Gaitan and is keen to add the Argentine playmaker to his squad when he takes officially takes over after the World Cup.
The Red Devils are willing to offer the Portuguese champions Bebe as a makeweight in the proposed deal for Gaitan.
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