Spurs' loss at the Emirates on Saturday dropped them to fourth in the table, 11 points behind league leaders Manchester City, and extended their woeful away record against fellow top-six teams to one win in 17 games.
"The season before, we were watching the draw and we thought: "Oh Monaco, Leverkusen and CSKA" and we thought we had a chance to go to the next stage", Pochettino said.
Tottenham, who are top of their Champions League group, have already sealed progression to the knockout stages and Pochettino believes their penultimate group match against a struggling Dortmund is the flawless opportunity to get a much-needed win.
Midfielder Christian Eriksen said: "We're still disappointed from Saturday, but we need to put it right tomorrow".
Having also been held to a 1-1 draw by Maribor in the reverse fixture, Spartak must now win their final group match at Liverpool next month if they are to avoid dropping into the second-tier Europa League after the winter break. That will free Pochettino up to make changes and he is likely to bring Harry Winks and Serge Aurier back into the team, and is considering recalls for Heung-Min Son and Danny Rose too.
"Everyone was down on us before the group".
"I agree that the English teams are looking much better in Europe this year and we hope we will follow this route to the end", he said.
Rose was left out of Mauricio Pochettino's squad for Saturday's north London derby defeat to Arsenal and the manager was afterwards forced to deny a rift with the player.
"He's doing well", Pochettino said at the pre-match press conference.
"I can not speak about the rumours".
"I will tell Dele to be careful if he is the referee". "Always it is important to be aware of the situation", he said.
"The objective was to qualify and we achieved that but it's important to finish first if we can". In the Premier League, we've made the second-best start since 1992.
"It means people expect more of us". Dortmund have a very shaky defense and Spurs are one of the best attacking sides in the competition so I think this could be a game full of goals. "It was a good ball from Dele [Alli] and thankfully I got it out of my feet and through the defender's legs".