Martino was named as Tito Vilanova's successor on Monday and received a glowing recommendation from the Argentina international.

The former Paraguay coach had been in charge of Newell's Old Boys in Argentina - the club Messi supported as a boy - and arrives at the La Liga champions on the back of a title win in his homeland.

However, Messi has quashed speculation that Martino was appointed on his say-so, but added that he supports the decision to bring him to the Camp Nou. 

"I had nothing to do with Martino's signing," he said, following Barcelona's 2-0 pre-season defeat to Bayern Munich on Wednesday. "It was down to president Rosell and the club.

"I said before that I thought he (Martino) was a good coach, but I do not have anything to do with this (his appointment).

"I do not know him personally, I've never met him. Not him nor Luis Enrique, the other one they've been talking about.

"I think he's a good signing, he showed at Newell's and with Paraguay what he's capable of. Hopefully he'll be good for us."