The centre half is a part of the Argentina squad for their upcoming international games.
However, Martinez is currently out with an injury and is not expected to play for some time.
Advertisement
Advertisement
Per The Mail, Martinez can travel to the United States for his nation's training camp this month.
He has United's blessing to do so, as he is not likely to feature in any of the games.
The goal may be to get him some time on the training field against high level players.