The Greece international remains optimistic about his side's chances of reaching the next round of the Champions League despite an uphill struggle beginning with Napoli at home
The Bundesliga side currently sit third in their section with six points from four games, trailing joint leaders Arsenal and Napoli by three points, and go into the clash with the Partenopei having suffered a 3-0 defeat to Bayern Munich on Saturday.
However, Papastathopoulos believes that, despite their well documented defensive problems heading into the tie and their three-game losing streak, Dortmund can still qualify for the last 16.
"We know we still have matters in our own hands and will not see that chance taken away from us," the Greek defender said at a press conference.
"I think all the players know what is at stake. We have had many talks since Saturday's defeat and are totally programmed on a win.
"It will be like a final for us against Napoli."
The last time that the two sides met was on matchday one and Napoli secured a 2-1 victory at the Stadio San Paolo.