New Barcelona coach Gerardo Martino has stressed the importance of keeping Lionel Messi fit during the season.

The four-time Ballon d'Or winner was substituted during Barca's 7-0 win over Levante in La Liga on Sunday.

"I discussed with Leo, he needs to rest every now and then," Martino told reporters. "Of course, when the game is tight, not even the biggest fool subs him.

"The season is long and there is a difficult series coming up. He's very intelligent, he knows that."

Messi scored twice during the opening day win.