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.