Cristiano Ronaldo believes Real Madrid's forthcoming tie is a real 50-50 © Getty Images Enlarge

Real Madrid's Cristiano Ronaldo is expecting an epic battle between super coaches Jose Mourinho and Alex Ferguson when Madrid and Manchester United square-off in the Champions League round of 16.

Ronaldo has been a disciple under both coaches, scoring 84 goals under Ferguson for the Red Devils before notching 133 goals in 122 appearances in the white of Madrid.

But when asked to answer who was the better coach, Ronaldo refused to draw a line in the sand, only predicting there would be no quarter asked - or given - when the two sides clash.

"It's not fair to say, it's like comparing a Ferrari with a Porsche," Ronaldo told The Sun. "Both are very good, very experienced and both like to win - and I mean to win everything.

"That's why they have both been champions many, many times."

An intriguing battle between two of Europe's biggest clubs, the clash not only pits Ferguson against Mourinho - strongly linked as Ferguson's long-term successor - but sees Ronaldo return to Old Trafford for the first time since leaving for £80million in 2009.

And despite recognising the pressure of returning in enemy colours, the Portuguese winger is relishing the chance to again dazzle in the Theatre of Dreams.

"Manchester was my home and still is in my heart," Ronaldo said. "I love it. Because when people treat you very well you never forget that. And I will never forget United, the people who work there and the supporters.

"For me it will be a pleasure, a real pleasure. Of course I know there will be a lot of attention on me but for me there is no pressure, no pressure at all.

"It is only a game, just a football match against my old club. I'm not going to war, I'm going home - and I am really looking forward to it."

Ronaldo said he even felt a certain air of inevitability he would be returning to Eastlands when the draw was announced.

"On the day of the draw I was out training and I had this strong feeling that we were going to get Manchester United," Ronaldo noted.

"And when the draw was made I was very happy. It's a tough match of course - Madrid and United are the two biggest clubs in the world and it's a real 50-50. It could go either way."

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