This surprise footage was obtained by a television channel in Argentina - and brought to our attention by 101greatgoals - and has since found its way on to YouTube. (Scroll down to see the video).
Messi, the Argentina captain, partially covered his mouth while speaking to his compatriot - but the cameras and microphones managed to pick up what both he and his teammate said.
“What was he saying in the dressing room, some nonsense?” Messi can be heard saying to Di Maria.
The Manchester United winger responds: “That it won’t be an easy result,” before the two superstars laugh.
Argentina surrender two-goal lead
Argentina were 2-0 up at the time, thanks to goals from Sergio Aguero and Messi, but conceded two second-half goals - including a 90th-minute equaliser.
Martino, therefore, was right to expect a tough second 45 minutes - but it seems not all of his players took his cautious words seriously.
Messi knows Martino well from their time working together at Barcelona last season; the current Argentina head coach was Messi’s dad’s favourite player thanks to his three spells with Newell’s Old Boys, the club Messi himself started his career before earning a move to La Masia.
It’s unlikely that Messi meant any malice towards Martino - the four-time Ballon d’Or winner has a great deal of respect for the former attacking midfielder - and this was surely just a light-hearted joke between two pals about their manager.
This must happen in every dressing room all over the world, but Messi and Di Maria should have been more aware that their every move was being recorded.
Argentina have work to do
Saturday’s 2-2 draw leaves Argentina with some work to do in order to qualify from Group B.
Next up for Martino’s men are Uruguay this evening, before a match against Jamaica at the weekend, which should be relatively straight-forward for the two-time world champions.
Argentina are under pressure to win the Copa America, having failed to secure a major trophy since 1993.
While they have some of the world’s most talented attacking players at their disposal, defensively they are a little suspect - and this could ultimately cost the Albicelestes in Chile this summer.
[Quotes translated by 101greatgoals]
Should Tata Martino take action against Lionel Messi and Angel di Maria for mocking his team-talk? Have your say in the comments below!