The former Argentina international had retired from professional soccer but remained active at a semi-professional level in 2012.
However, the former Manchester United and Inter midfielder has stepped in to help out at the club where he began and ended his professional career. Martinez has welcomed his impact and influence within the squad.
"It is great that Veron has returned and it is great for Argentine soccer too," he told Ole. "If he can become part of the team it would be great for a team like us that has so many young players.
"I am surprised by his return, he is from another time in footballing terms. But he will help us. With a player like he is in the team, his presence will push us forward. Hopefully it will be good for us all. He is training with us and is on par with us. He is doing well."
Estudiantes has suffered a woeful start to the season having picked up just four points in nine matches. It is also not taking part in the Copa Libertadores this year, a competition it won in 2009 with the help of Veron.