Erik ten Hag is eager for the club to follow up the signing of Tyrell Malacia this week with the arrival of Martinez, his top defensive target this summer.
While Arsenal are also in the race for his signature, it has been claimed the Argentina international would favour the opportunity to reunite with his former Ajax manager at Old Trafford.
While one of the best defenders in the Eredivisie, Martinez stands at 5ft 9in, shorter than many of the Premier League’s towering centre-halves with Virgil van Dijk 6ft 3in and his potential teammate Raphael Varane at 6ft 2in.
And Ferdinand has concerns how the 24-year-old will measure up against some of the leagues bigger centre forwards.
‘Martinez, left footed, very good on the ball, a very good distributor of the ball,’ Ferdinand told his Five YouTube channel.
‘There are still going to be question marks about him. Is he quick enough? Is he big enough? Is he going to be dominant enough in a league that demands your physicality being tip top? You’ve got to be ready physically to play against these big strikers.
‘[Darwin] Nunez and [Erling] Haaland have just gone into the big teams at Liverpool and Man City. They are over six foot, he is going to have to deal with people like that on a regular basis.
‘Chris Wood at Newcastle, these are big, big guys, you can go through the league and find players of this ilk. Will he be able to deal with people like that because physically, he’s on the smaller side for a centre half.
‘He has got other attributes, he’s aggressive, he’s a leader, he takes the ball comfortably. So there are pros and cons.’
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