The forward withdrew from Argentina's squad ahead of their 2-1 victory over Italy on Wednesday after picking up the muscular strain during the Blaugrana's preseason tour of Asia.
Messi has focused on his rehabilitation with the club's medical staff during the week in order to be fit to feature at Camp Nou on Sunday, and new coach Gerardo Martino has chosen to name him in the 18-man squad.
"Messi is very enthusiastic," Martino said in a press conference ahead of the game. "He has been working hard during his holiday. There are always records to break and trophies to win."Cesc Fabregas, who has been linked heavily with Manchester United during the summer, also makes the opening Liga matchday squad, though captain Carles Puyol is yet to regain full fitness.
Martino insisted that despite Puyol's lack of fitness Barca would now not be in the hunt for another defender, having ended the club's pursuit of Chelsea's David Luiz and Liverpool's Daniel Agger.