Borussia Dortmund midfielder Mario Gotze told reporters that his side's narrow defeat of Union Berlin did not go according to script on Wednesday.
Dortmund progressed to the quarterfinals of the DFB Pokal after beating second division side Union Berlin 4-1 on penalties (1-1 in regular time), and Gotze confirmed the cup match ahead of Saturday's Revierderby against rivals Schalke 04 did not happen as Thomas Tuchel's team had planned.
"We imagined the match to go differently," Gotze said. "As long as we're only up by a 1-0 lead, the opponent can always be a threat. We saw that once again today."
The Ruhr Side had controlled the match with a narrow 1-0 lead that came by Union Berlin midfielder Michael Parensens, who deflected the shot of 18-year-old debutant Jacob Bruun Larsen into the net for an own-goal in the 44th minute.
Steven Skrzybski shocked the hosts with a clanger from distance in the 81st minute to tie the match, forcing the cup match to be decided by spot kicks.
"It was unfortunate to concede such a goal," Gotze said on Skrzybski's lucky punch towards the end of regular time.
However, the German international conceded that his team has only themselves to blame for the extra 30 minutes: "We had enormous chances. We have to learn to make more out of the opportunities that present themselves. Had we doubled the lead early, the match would have taken a different course."
He added: "Things don't always go the way you plan in football, but we should have forced the issue sooner. In the end, we're happy that we managed to advance to the next round."
Dortmund will host Union Berlin's city rivals Hertha Berlin in the round of 16. The match will take place in February 2017. The Black and Yellows, however, have little time to worry about the following cup match, as they will face their rivals Schalke at home on the weekend.
After three winless games in the Bundesliga, Dortmund have dropped down to sixth place. The pressure is already mounting ahead on Tuchel's young team, making the derby an even more crucial match for them.
"For us it's important that we threw everything into today's match towards the end. With today's win we can head into Saturday's match with confidence," Gotze said about the awaited match against Schalke, who sit in 14th place after only taking four points out of the first five league matches.
He added: "It's an important game and we will do everything to come away as winners."
However, Markus Weinzierl's side will arrive at the Westfalenstadion with the confidence, having won five out of their last six matches across competitions.