Arsenal boss Arsene Wenger is still angry over their Champions League defeat to Liverpool last season.
"We were [the better team over the two legs]," insisted the Arsenal manager.
"I feel that we were guilty of not being focused when we scored the second goal [in the second leg] and we paid for that.
"We were a bit unlucky too because we should have got a blatant penalty on [Alex] Hleb in the first game [at Emirates Stadium] and there was no blatant penalty on Babel in the second leg."