Lisandro Martinez joined Ajax in 2019 from Argentinian side Defensa for a fee of £6.3mManchester United are in advanced discussions with Ajax over defender Lisandro Martinez, and a deal could be concluded as early as Thursday.
Talks to sign the Argentine, 24, have moved forward over the past few days.
It is believed that Martinez, who has also been linked with Arsenal, is eager to make the switch.
Martinez could become the club's second signing under new manager Erik ten Hag, after the arrival of Tyrell Malacia on a four-year deal from Feyenoord.
United are yet to confirm that Christian Eriksen has signed his contract.
The centre-back, who has made seven appearances for Argentina, joined Dutch side Ajax in 2019 and has played 120 times for the club.
