#3 Positional Clarity
Apart from brief flashes now and then, Cristiano Ronaldo - the winger, is dead.
Also Read: Cristiano Ronaldo, an elastico, and the beauty of a singular moment
As he ages, Ronaldo knows he cannot beat a marker with the same ease anymore. Being the ever intelligent footballer, Ronaldo plays far more centrally now than before - and it's working. He may not have the same contribution over 90 minutes, but when the decisive moment comes, the Portuguese superstar is there. His evolution into a central striker might just be completed tonight.
In contrast, Lionel Messi is enjoying a fairly great season personally, but the Argentine's shift towards a deeper role in the last few months may work against him tonight. He looked a supreme creator in this role against Juventus in the UEFA Champions League, but the simple fact is that Barcelona did not score in 180 minutes against the Italians.
Taking Messi away from the front line imbalances Barcelona's attacking play, and its a waste of his talents. In addition, playing Messi deeper makes it easier for Casemiro to man mark him and retain Madrid's defensive shape.