The Argentine returned to training with the squad on Tuesday and admits he was delighted to return to pre-season preparation with his club under a new coach
The Catalans ended the 2013-14 campaign under Gerardo Martino without a major trophy and Messi went on to suffer World Cup final heartbreak as Argentina lost 1-0 to Germany.
The Argentine returned to full Barcelona training on Tuesday and afterwards said he is already looking forward to the new campaign.
Barcelona take on Napoli in a pre-season friendly in Carouge on Wednesday.
They begin their Liga title challenge at home to Elche on August 24.