Real Madrid boss Zinedine Zidane heaped praise on Karim Benzema after his compatriot inspired the European champion to a 3-1 Champions League comeback victory over Napoli on Wednesday.

The first-leg victory put Madrid on the brink of a seventh successive European Cup quarterfinal as it aims to become the first team to retain the trophy in the Champions League era.

Lorenzo Insigne's clever 40-yard strike after just eight minutes gave Napoli the early lead at Santiago Bernabeu.

However, Zidane was rewarded for keeping faith in Benzema despite fierce recent criticism of the French striker in the Spanish press.

The ex-Lyon forward headed home his 51st Champions League goal to equalize before second-half strikes from Toni Kroos and Casemiro gave Madrid a commanding lead.

"I am always happy with him (Benzema)," said Zidane.

"He needed that goal which lately he didn't get, but I am happy not only for the goal but also for how he played.

"He made the rest of the team play better and his movement is very good. The performances of Karim, Cristiano (Ronaldo), James (Rodriguez) all made the rest of the team better."

But Zidane warned his squad still has everything to play for in the return leg at Stadio San Paolo on March 7.

"We'll go there to a difficult ground where we'll suffer and it's still an open game," Zidane added. "We need to go there and finish it off."

Benzema's strike moved him ahead of Thierry Henry as France's all-time top scorer in the Champions League.

"It was a great night. We all played well, not just me," Benzema told TV station MEGA.

"I am very happy and proud of my work. I scored and saw the fans were with me, which is good for my confidence."

Napoli's Dries Mertens blazed over with the goal at his mercy and Jose Maria Callejon had a goal ruled out for offside.

However, Napoli boss Maurizio Sarri said his side can still reach the quarterfinals for the first time in its history.

"Clearly Madrid played their best game of the past three months and we didn't play our best," said Sarri.

"If we manage to play at our best, we are not that far away. We may lose (in the second leg) but we can go for it.

"It is the first game we have lost in four months. We didn't manage to express ourselves 100 percent, but we can't lose our confidence because we have the return game and league games to come.

"We don't have a great chance of turning it around but we have a chance."

Former Napoli great Diego Maradona gave the Italians a pre-match pep talk, and Sarri believed his team's fast start justified his decision to invite the Argentine into the locker room.

"Diego spoke with us for 30 seconds, but he is a legend so clearly it had an impact. Our first 10 to 15 minutes were our best."

Sarri, though, lamented his side's distribution from the back under Real's intense pressing.

"It was difficult to counter attack because we gave the ball away so much," he said.

"We were playing a very good team, the best team in the world. The only thing is I think we committed more errors than normal."

Weary Wenger bemoans frailties

Arsenal manager Arsene Wenger said his side "collapsed mentally" in its 5-1 Champions League loss to Bayern Munich on Wednesday.

The Frenchman said there were no excuses as the Gunners faced a seventh straight last-16 exit after their latest mauling.

"We conceded the second goal and then the most important thing was that we lost Laurent Koscielny (to injury). We collapsed mentally," said Wenger who will now face fresh calls for his resignation.

Wenger's post-match media conference lasted barely five minutes after he cut it short, answering just a few questions.

"I am not looking for excuses. Overall, I must say they were a better team than us, they played very well in the second half and we dropped our level," he said.

"They were better than us, well done to Bayern. Their third goal was a killer - we had no response. It is a shock, of course, to lose at this level."

Wenger was evasive when quizzed about his mood after the match.

"How I feel I don't think is the most important but of course it is disappointing," he said, although pundits thought otherwise.

"He looked particularly wounded. I feel for him - he almost needs to be protected from himself," former Arsenal defender Martin Keown, who played under Wenger, told BT Sport.

"It's a massive low point for him. This brings forward the change that looks likely at the end of the season."

Wenger said the loss of France international centerback Koscielny after the break, with the score 1-1, was a turning point.

"I'd have loved to have kept Laurent on the pitch and it's difficult to measure the impact, but we have to cope with the result," said Wenger.

"It was difficult to shake off two goals in quick succession - we lost our organization and our centerback.

"We were badly done for the second goal (Robert Lewandowski's header) and the real problems came after the third because we lost our organization.

"The last 25 minutes were a nightmare for us."

Real Madrid's Karim Benzema is sent flying as he collides with Napoli goalkeeper Pepe Reina during the Spanish side's 3-1 Champions League last-16 win on Wednesday. Reuters / Susana Vera