'Kun' the potential key for City

Sergio Aguero has a proven scoring record against Barcelona and the Manchester City forward may have a crucial role to play if his side is to upset the odds and reach the Champions League quarterfinals for the first time.

City trails 2-0 ahead of Wednesday's last-16, second leg at the Nou Camp, a Lionel Messi penalty and a late Daniel Alves goal in Manchester last month put the Spanish champion on the brink of its seventh consecutive appearance in the last eight of Europe's elite club competition.

Aguero, who missed the first leg through injury but returned for City's English League Cup final victory on March 2, scored five goals in 10 La Liga games against Barca for Atletico Madrid between 2006 and 2011.