The reigning Premier League champions returned to the top of the domestic table courtesy of yesterday's 5-0 thumping of Aston Villa and now they need to take that form into the Champions League as they tackle the Spanish champs in a must-win fixture.
City sit at the foot of the Group D table and desperately need to win this outing before taking down Borussia Dortmund on Match Day 6 if they are to qualify for the knockout phase and Aguero is well aware of the enormity of the task ahead.
"It's a good game," said Aguero. "The truth is we have to win so we are going to go out and win however we can.
"We will have to see the other results but in the meantime the important thing is to play how we have been doing and do our best to win."