Martinez met his new team-mates this week after Manchester United’s squad returned from their pre-season tour and reunited with his former Ajax coach Erik ten Hag.
The Argentine has also travelled to Oslo for Manchester United’s pre-season game against Atletico Madrid on Saturday.
Manchester United agreed to pay a fee of €57.32m to Ajax for him and will fork out €10m in potential add-ons.
And according to Dutch daily De Telegraaf, the add-ons are easily achievable, based on his appearances for Manchester United.
The €10m add-ons are based on each official appearance the defender will go on to make for the club.
Ajax will receive a fee of €66,667 for each appearance the new Manchester United boy makes until the €10m mark is hit.
Martinez is likely to wear the red shirt for the first time against Atletico Madrid in Oslo on Saturday.
However, Ajax will not receive a fee for that as it will only be pre-season friendly for the Red Devils.