Already the match seems to be a very though one for both teams because since Real Madrid have already won the first leg they would just play to secured a draw against Manchester city. But with the recent performance of Manchester city against Newcastle united in the premier league last week I think they might likely secured a win against Real Madrid tonight, because they would going to play the game with full force to win and qualify for the next round.
Why do you equate Newcastle United with Real Madrid in different competitions? It becomes even stranger if you consider the Premier League competition the same as the Champions League competition 
. Because if you want to compare the strength of Manchester City this season with its strength last season, I think you will find quite a big difference in the Manchester City team itself. While Real Madrid is still dubbed as the ruler of the Champions League because last season the team also succeeded in becoming champions in the Champions League after slaughtering Dortmund in the final match.In this match, Pep Guardiola will be careful and does not want to be too optimistic ahead of the second leg between Man City and Madrid. He may be worried that Madrid will use a more aggressive and risky strategy, like Ancelotti did, to turn things around. So Pep may want to make sure that his team is ready to face the challenge and will not be surprised by Madrid's strategy.
For now, both teams are experiencing something very vital in their teams, namely injuries. Both teams are recovering to play consistently in order to win and play well. We'll see tonight whether Ma City will make a comeback or Real Madrid as the one who has the competition to show their throne? What is certain is that in this big match there will be many miracles that will happen at the Bernabeu.