Arsene Wenger has said that Arsenal were not efficient enough during their 2-0 defeat to Chelsea in the Capital One Cup this evening.
A goal in each half for Jose Mourinho's side was enough to see them through to the quarter-finals of the League Cup.
"Nothing is evident tonight because I felt we played quite well but we were not efficient enough especially defensively and it made it difference from then on. It was a tight game and they took advantage of our mistakes," BBC Sport quotes the Gunners manager as saying.
It is the first time that Arsenal have not reached at least the last eight in the tournament since the 2002-03 season.