The first week in October is a little early to be talking of must-win games, but in a group of death you never live twice. The shadow of defeat by Real Madrid hung like the rain-laden Mancunian clouds over the marquee in which Roberto Mancini and Yaya Touré were asked to once more pick over the last few chaotic moments in the Bernabeu.
"I don't need to learn," said Mancini when pressed on a managerial record in Europe that, at Internazionale and at Manchester City, is at odds with a CV full of domestic success. "The Champions League is a difficult competition, but the football is the same, the players are the same, it is still 11 versus 11. The problem is that you play the best teams from other countries. Every game is difficult.
"I think the time will come when we can win the Champions League but in this moment we are in a difficult group. Sometimes, when you play in the Champions League, you should be lucky with the draw. It is important for us to get into the second stage because, after that, anything can happen."
The 3-2 defeat in Madrid proved precisely what can happen when focus is lost, however briefly, against one of the big beasts of European football. "With five minutes to go, we were 2-1 ahead and we made some mistakes," said Mancini. "When they scored their second we went too deep and we conceded a lot of space. If you concede space to [Cristiano] Ronaldo and [Karim] Benzema, you are taking risks."
And the City manager warned: "If we concede space to Borussia Dortmund, it will be hard.
"We are as good a team as Manchester United and Arsenal. Look how we have improved in the Premier League. I think we need time to improve in the Champions League but we do not have time – we have only five matches and we cannot concede goals like we did against Real Madrid. If we want to go through, we have to improve quickly."
There is plenty that links Dortmund and Manchester City. Both have supporters of rare passion, both have broken out of the shadow cast by rivals with more glamour and financial clout – Dortmund not only beat Bayern Munich to the Bundesliga title, they retained it.
While their last visit to Manchester ended with them overcoming United at Old Trafford, a result that left Sir Alex Ferguson dumbstruck and Dortmund in a European Cup final, neither has cut it in the Champions League. Dortmund finished bottom of their group last season while City's 10 points failed to see them through to the business end of the competition.
Perhaps because at Barcelona he was used to so much more, Yaya Touré labelled the campaign "a disaster" rather than the near miss it was. "Look at our rivals," he said in an interview with Champions magazine. "Chelsea and Manchester United have appeared in finals and this year I think we can go far and even win it." He did not, however, disagree when it was put to him that this was a "must-win match".
There is another similarity between the two clubs: both have been stricken by the prospect of insolvency. However, while Manchester City were rescued by intervention from Abu Dhabi, Borussia Dortmund dragged themselves clear largely through the efforts of their general manager, Hans-Joachim Watzke. "We are not in the business of taking money from a sheikh," he said before this evening's game. "We want to keep our soul."
He added: "Were Sheikh Mansour to come to Dortmund [to invest], I would not entertain him. What if he lost interest, as the sheikh has done at Malaga? Then, everything becomes critical. The Bundesliga has caught up considerably with the Premier League through its sound banking practices. This will eventually be expressed in results on the pitch."
Nevertheless, many among Jürgen Klopp's squad are not especially confident of obtaining a positive result on the pitch they trained on last night. Whereas the Dortmund side that won the European Cup in 1997 was based on hard-working, uncompromising play, epitomised by the likes of Paul Lambert and Paulo Sousa, this is a team of wonderful flair but it is also young and potentially brittle.
As City were being eliminated from the League Cup last Tuesday by Lambert's Aston Villa, Klopp was being sent to the stands during a frantic 3-3 draw with Eintracht Frankfurt. Their captain, Sebastian Kehl, talked of having to stand strong in the face of City's potentially "brutal attacks".
Some of Klopp's players were part of the German squad that lost the European Championship semi-final to the brilliance of Mario Balotelli. If the ghost of Madrid has not been entirely exorcised in Manchester, then the echoes of Warsaw's National Stadium may continue to follow Hummels, Götze and Reus.
Dortmund danger men: Four City need to watch
There were many reasons why Borussia Dortmund won the Bundesliga last season but it is hard to look past Lewandowski's 30 goals. His first season in Germany had not been a success but once he found his feet, Lewandowski proved irresistible. The €4m that it cost to bring the striker to the Westfalenstadion from Lech Poznan on a four-year contract must count as one of the great bargains of European football. When in the summer Chelsea asked about his availability they were quoted a fee of £35m.
That one of German football's most dazzling talents decided to remain with Borussia Dortmund rather than accept one of the many offers to move abroad says plenty for the growing strength of the Bundesliga, although Nuri Sahin's failure to make any impact after going to Real Madrid may have served as a warning. Götze had joined the club as an eight-year-old in 2001. His main strengths are speed and technical ability that have won him 18 caps for the German national side, although it was a surprise he was left on the sidelines for so much of Euro 2012.
An elegant, intelligent centre-half, Hummels was one of the great successes of the German campaign in the European Championship. A good a judge as Ruud Gullit thought him perhaps the player of the tournament. The 23-year-old was part of Bayern Munich's youth set-up, where his father worked. However, he failed to make a breakthrough and was sent on loan to Dortmund in 2008 where he flourished, signing a permanent contract a year later. Just before Euro 2012, Hummels signed a five-year contract that ended interest from Bayern Munich, Manchester United and Barcelona.
Nothing quite demonstrated the shift in power in German football than the 23-year-old winger's decision to go to Borussia Dortmund rather than Bayern Munich in the summer, which caused outrage and accusations of betrayal at the Allianz Arena. Reus dazzled in the European Championship quarter-final against Greece, a performance that summed up a potential that came to prominence at Borussia Monchengladbach, for whom he scored almost 40 times in 97 appearances. His fee of £15m was not eye-opening but his destination was.
Kick-off 7.45pm, Etihad Stadium (Sky Sports 2)
Referee P Kralovec (Cz Rep)
Odds Man City 5-6 Draw 13-5 B Dortmund 10-3