Sir Alex Ferguson has admitted Cristiano Ronaldo is a better player now than when he left Manchester United.
Four years after United pocketed a world record £80million from Real Madrid for the Portugal superstar, they find Ronaldo standing between them and Champions League progress.
The Red Devils have every right to be fearful.
After all, Ronaldo contributed an incredible 42 goals to United's Champions League-winning campaign in 2008.
And he has improved at Real.
"Cristiano is a better player than when he left us because of his maturity," said Ferguson.
"He is at the peak of his career now.
"He was still a young man when he left and you can see how he has flourished in Madrid.
"His fitness, speed, goals - and he's never injured. That is unique in the modern game.
"I never thought he'd get the amount of goals he's scored.
"I knew he'd improve. I knew he was one of the best players in the world. But to score the goals he has is phenomenal."
Yet Ferguson still feels his squad is good enough not only to cope, but challenge for the trophy.
Two seasons ago, in their third Champions League final in four years, United were comprehensively swept aside by Barcelona.
Many of the faces remain - only Edwin van der Sar and Fabio of the team that started that 3-1 defeat have left Old Trafford.
But new blood has been injected in the form of David de Gea, Tom Cleverley, Danny Welbeck and Ashley Young.
Most importantly of all, Robin van Persie has arrived to give United the additional firepower required to compete at the highest level.
Tonight against Madrid, Ferguson will find out if they are the real deal.
"Our team is capable of winning the Champions League," said Ferguson.
"There is a great spirit about them.
"People keep saying we're not as good as past United teams but then sometimes we get foggy impressions about the past. I do so myself at times.
"But the reality is this team doesn't know when it is beaten, which is a great quality.
"I have no doubt in my mind the acid test is [tonight].
"It's unfortunate we're meeting this early. I wish it had been at Wembley.
"But we can't think of failing. We have to get through if we are to win this trophy."