Barcelona playmaker Andres Iniesta has admitted that his side "will have to play our best football" if they are to advance beyond Manchester City in the first knockout round of the Champions League.

The two teams will meet at the Etihad Stadium this evening, before a return clash in Spain next month.

Looking ahead to both encounters, Iniesta believes that the champions of England are sure to be a "really demanding" opponent.

"Manchester City is a great team that has signed really good players this year. Against these rivals and taking into account that we are in the Champions League qualifying stage, it's these details that could make the difference," he told Nissan, the competition's main sponsor.

"The two games will be really demanding and we will have to play our best football."

Barca and City met at the same stage of the competition last term, with the Catalans running out 4-1 winners on aggregate.