United have turned to the unsettled Arsenal defender after failing to agree a fee for World Cup winner Mats Hummels.

But the Old Trafford outfit will have to fend-off strong interest from Barca if boss Louis van Gaal is to land Vermaelen.

The Spanish giants are poised to make a £10m bid for the Belgium international, who wants to leave the Gunners due to lack of game time.

But United's failure to land Borussia Dortmund star Hummels has piled the pressure on chief executive Ed Woodward to land an alternative.

Van Gaal is desperate to strengthen the centre of his defence following the departures of Rio Ferdinand and Nemanja Vidic.

It seems United are prepared to outbid Barca for Vermaelen and offer him bigger wages than the Spaniards.