"The tie is still alive but we need a big performance in Turin," Capello told Tuesday's post-match press conference in London.

"We played well in the first half until Arsenal scored a goal we should not have conceded, and the second goal could also have been avoided."

The Serie A champions stayed on their feet for 40 minutes when Cesc Fabregas notched the opener before they collapsed after the break, conceding another goal and finishing the game without even one missing chance.

Capello said that Arsenal's postponed game against Portsmouth helped Arsenal appear sharper.

"After that, Arsenal played very well and they were very fresh because they had not played a match for nine days," he said.

The second leg will be played at the Stadio Delle Alpi next week.