Rolfes said that he and his teammates need to regain their motivation and focus for the return leg and if they do then "all is not lost".
"If you lose at home in the Europa League 1-0, it is not a favourable situation," Bundesliga.de quotes Rolfes as saying.
"However all is not lost; we have already played well away in Europe this season. Our problem is that we play well and create a lot of chances, but cannot score.
"We are perhaps a bit unfocused and not motivated enough. If we change this then we have a chance in Lisbon."
Rolfes has made 24 appearances this season for Leverkusen.