Both forwards have forged a strong bond at the club level for Paris Saint-Germain but will keep their friendship aside for the biggest prize in football.
Argentina began preparations for the title match on Thursday night. Their players took part in a training session, but Messi was missing from the group.
His absence led speculation about a possible hamstring injury. But reports stated that Messi, and other players, were given extra rest after their semi-final win over Croatia.
Meanwhile, Antoine Griezmann said playing Messi is "a totally different proposition" to anything else they have faced in Qatar as France gear up for their World Cup title defence.
Messi, 35, has dazzled in what will be his last World Cup match.
"Any team with Messi in is a totally different proposition." Griezmann said. "We have seen practically all of their matches at this World Cup.
"We have seen Argentina play, we know how they play. They are a difficult team to play and they seem to be on top form.
"Of course, not only Messi, they have a strong side around him so we know it is going to be a tough game and they will have a lot of support in the crowd.
"We will get back to work tomorrow, focused on it, how we can hurt them, how we can defend against them. We will be well prepared."