The former Newell's Old Boys boss was appointed as Tito Vilanova's successor on Tuesday, signing a two-year contract with the La Liga champions. 

Martino won the Clausura title in his native Argentina with Newell's last season and received a glowing endorsement from Lionel Messi prior to his appointment at the Camp Nou. 

The 50-year-old has never managed outside South America, but admitted he was looking forward to the challenge of leading one of the biggest clubs in Europe. 

"Barcelona's call surprised me, I didn't expect it, I was planning to start a sabbatical," he said. "I'm grateful to Barcelona for believing in me.

"We want to add something to the team as a whole and to the players individually.

"Every coach hopes of making this step. Now we will try to adapt quickly and to live up to the expectations.

"Barcelona have a clear way of playing for years. We will have to adapt to that and make that style our own."

Messi, a Newell's fan, gave his support to Martino on Monday and the new manager is relishing working with the world's best player, adding that he is not sure when he will first take charge of his new side. 

"I'm sure the Messi family gave a positive advice, but I don't know to what extent that influenced the decision to sign me," he added.

"Coaching Barca means coaching the world's best. While working with Leo every day, we'll find the way to help him to stay the best.

"I don't yet know when I will be in charge of my first game. We will discuss that later with the club."