Messi was disappointing in defeat to Real Madrid on Saturday.
When asked about Messi's form of late, Guardiola said, "Allow me to never have to be concerned about Messi. Even if he doesn't score for 27 matches. Give him tranquility and the right to not have to score goals until he wants to. He's scored a brutal amount of goals this season.
"Let him play, be happy and be who he's always been. His ambition helps us all."