Pep Guardiola: I don't know what instructions I can give to control Lionel Messi

"Ninety minutes is a long time. They don't need to create a lot of chances to score a goal."

Pep Guardiola admits he does not know what to say to his Manchester City players to stop Lionel Messi.

City face a stern test of their Champions League credentials, and their progress under Guardiola, as they take on the Catalan's former club at the Nou Camp on Wednesday night.