Xavi's team are currently second in Group E and would be guaranteed a spot in the last-16 stage of the competition if they win at Allianz Arena.
Barcelona could lose and still go through if Benfica do not overcome Dynamo Kiev in the group's other match on the same night, but Memphis has insisted that his side cannot take any risks and must be fully focused on picking up all three points in Germany.
"It's our last chance to progress to the knockouts, it's like a final," Memphis told Barcelona's official website. "We have to mentally prepare ourselves to give our all and get the result."
The 27-year-old has been a regular for Barcelona this season following his arrival over the summer, making 20 appearances in all competitions, contributing eight goals and two assists.
The Netherlands international is yet to provide a goal or an assist in the Champions League this season, though, drawing blanks against Bayern, Benfica and Dynamo Kiev.