First blood at the Santiago Bernabeu on Saturday went to Barca, as debutant Luis Suarez set up in-form forward Neymar for a fourth-minute opener.
Ramos' Spain international colleague Gerard Pique then handled, allowing Ronaldo to maintain his record of netting in every league game this season 10 minutes before half-time.
Pepe brought the Bernabeu to its feet with a 50th-minute header before Karim Benzema capitalised on one of many razor-sharp Real counter-attacks to seal the three points.
The result closed the gap between Liga leaders Barca and Real to a solitary point and Ramos told reporters: "I'm very happy. The team was great in all areas and in all aspects, despite the goal conceded.
"We had very clear ideas and we dominated. Not only when we had the ball but on the counter-attack too. It was a very complete performance.
"Football is a game of stages and you have to know how to react. We managed to do that and we coped.
"We didn't only play on the break but we entered their half, had possession and they're not used to that and we hurt them."
Pepe's vital goal came from a Real corner and the hosts sprung forward from a Barca set-play for Benzema’s 61st-minute clincher, leaving Ramos highly satisfied with his side's work in both boxes.
He added: "We have to continue to improve how we defend corners. This time it went for us and Pepe got a gift and scored a good goal."
‘He instantly popped into our ratings as one of the best U21 midfielders in Europe. The impressive thing is Slot has made him into more of a no.6' Inside Ryan Gravenberch's transformation at Liverpool
‘I don’t think Liverpool would look at Ollie Watkins, a striker isn’t a pressing issue for them – it’s Arsenal who need one’ Former Reds star explains why his old club don’t need an out-and-out forward this summer
