Former Bayer Leverkusen striker Erik Meijer believes that the Bundesliga club must improve defensively if they are to stand any chance of progressing through to the knockout stages of the Champions League.
Roger Schmidt's side only lost 1-0 to Monaco on matchday one, but domestically they have conceded nine goals in just six outings.
With that statistic in mind and ahead of tomorrow's European encounter with Benfica, Meijer has urged the team to tighten up at the back.
"It will be very tough for Leverkusen. They will have to do better and also think about their defence. They lose their heads too quickly when they are dispossessed," he told Bild.
Leverkusen have won none of their four previous clashes against Benfica.