"He's a player who came to help and obviously he's helping a lot. He has a lot of confidence in himself, that's the main thing. He knows his ability and then he has a lot of confidence.

"When he is not playing, obviously he is not happy, but when he is playing, he wants to show the quality and the confidence he has."

The victory was just Newcastle's third in the league at St James' Park this season and their biggest since they defeated Chelsea by the same score on the final day of the last campaign.

Benitez, who had always believed his side's fortunes would turn, said: "Against these teams, if we work hard and we play at this level, you can get something. Sometimes it will be three points and others, it will be a draw, but at least you can get something.

"Always I say against the top sides, sometimes doing so well, it's still not enough. But against these teams, if you play well, you can win."

Opposite number Neil Warnock was disappointed with the manner of defeat, but vowed that his team would bounce back after seeing the Bluebirds slip back into the bottom three.

He said: "Nobody will expect us to bounce again, but we have shown all season that we have bounced back from adversity.

"It's not been an easy season for me – 94 minutes in front, that's all we've been. On the bench, that's the only time I've been able to enjoy it, 94 minutes.

"It should be allowed, should it? It's a health risk, isn't it, that?"

Meanwhile, Warnock confirmed that skipper Sean Morrison had undergone emergency surgery after suffering a burst appendix.

He said: "He was bright last night – I spoke to him last night – but he was a lucky lad, really.

"If his wife hadn't have been on the ball – she rang our club doctor, Len Nokes, and explained the symptoms and he said, 'Get yourself down straight away'.

"He arranged for the surgeon to see him and he was done straight away. He was a lucky lad, really."

Warnock also revealed that Nantes striker Emiliano Sala is close to completing an £18million switch to the Cardiff City Stadium after completing his medical.

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