Sergio Ramos said he was obviously happy to see bitter rivals Barcelona lose in the Champions League as he basked in Real Madrid's success.

There is no secret of the mutual hatred between Madrid and Barcelona, and the European titleholders from the Spanish capital were able to watch on in delight as the Catalans suffered a humiliating 4-0 defeat to Paris Saint-Germain on Tuesday.

Barca have a mountain to climb heading into the second leg of their last-16 tie, while Madrid are in the box seat following Wednesday's 3-1 win at home to Napoli.

Asked if he was happy about Barca's defeat in Paris, captain Ramos told reporters: "I won't say no.

"I don't like to see my friends suffer, but obviously I don't like Barcelona to win."

Former Madrid winger Angel Di Maria inspired the rout at the Parc des Princes, scoring twice on his birthday, but the humbling did not come as a surprise to Ramos.

"I wasn't [surprised]," he added. "What it means is that in Champions League any team pays for a bad game. PSG did a great game, put pressure in the front."

As for Madrid, the LaLiga leaders are on track for the Champions League quarter-finals.

After Lorenzo Insigne gave Napoli a surprise lead inside eight minutes, Karim Benzema, Toni Kroos and Casemiro all scored in front of the Santiago Bernabeu faithful.

Madrid, however, will be sweating on the fitness of Ramos, who hobbled off with a leg injury 19 minutes from time.

"I suffered a blow and I hurt my hip and adductor, I held on as I could until I thought the result was good, to wait for the tests," the Spanish defender said. "Hopefully it's not anything muscular."