With the return of the Champions League, James Richardson and Goal.com's panel of experts discuss the key talking points at Wembley
The Portugal international will come face-to-face with the Premier League giants since his £80 million exit in 2009 and speaking at Wembley alongside James Richardson and Goal.com International football writer Paul Macdonald, Greg said: "You do feel Ronaldo will come back to haunt Manchester United because that's the kind of player he is."
"He knows how to score in the big games and United's defence has not been good this season at all. They've conceded first in their last five European games."
Heading into the game, one of the biggest talking points has surrounded Real Madrid's poor league form, leading to questions regarding Jose Mourinho's future at the La Liga side.
With this in mind, Paul Macdonald spoke of the important surrounding Champions League glory for Los Blancos.
"The situation with Mourinho is clear, he's put all his eggs in the Champions League basket and he knows delivering La Decima at the end of the season will be the ultimate parting shot after months and months of political and player issues," he said.
"I think Mourinho knows facing one of his old adversaries in Alex Ferguson and defeating him would be one of his greatest achievements. I think he also knows that if he's to fail Real Madrid could pull the trigger early on his Santiago Bernabeu reign."
Do you think Ronaldo will be the difference between the two teams? Would defeat for Madrid leave Mourinho without a job? Let us know your thoughts.
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