Federico Valverde scored a first half hat-trick for Real although a penalty save from Gianluigi Donnarumma against Vinicius Junior offers City slight hope for the round 16 second-leg.
A delighted Arbeloa said afterwards: “It was the match where we followed our plan the most. We were a team in capital letters, which is what we need to win any game. From day one, I said that this locker room is full of great players, but we also need to be a great team to beat Manchester City or Elche.
"That’s what I need my players to believe: they must be a team, have a collective mentality, and be clear about what to do when we don’t have the ball and when we do. They are players with exceptional quality, but even better if they all share the same idea and follow it as they did today.”
“I’m very happy for the fans because they deserved a night like this after the season we’re having. They enjoyed it a lot, and I’m happy for my players because it’s not easy to manage everything they’ve had to deal with. We know the demands of Real Madrid, but there are many circumstances that aren’t helping us.
"Very happy for the effort, for the work they’ve done, because they believed in themselves and pushed non-stop. They deserved a night like this. It seems like we’re celebrating, but we still have 90 minutes of great suffering in Manchester, and that’s the first thing I told them. It’s not over.
"I know and they know the players in the opposing locker room well, the atmosphere that always exists in Manchester, and the coach, who will analyze the game 747 times. We have 90 minutes of a tough battle ahead if we want to advance.”
The new Juanito
On Valverde, Arbeloa paid the midfielder a major tribute.
He also said, “Very happy for him. Many times, I have thought that in the end, he might end up hating me for being so insistent with him and for the constant talks I have with him to convey how important he is for the locker room. He is the Juanito of the 21st century. He is a player who perfectly represents what Real Madrid is.
"He is one of the leaders and will continue to be for a long time. If the fans feel represented by someone, it is him. The night he had today fills me with pride because he deserves it, and it is a reward for all his sacrifice, for pushing forward when things go wrong, for always being the first, for leading by example, and for leading in the way he does.”
Juanito played 10 years for Real Madrid, with the midfield great winning five LaLiga titles.