The Argentina international joined the Serie A runners-up from La Liga giants Real Madrid as a replacement for Edinson Cavani.

He is set to feature for the club against Arsenal in their opening fixture of the Emirates Cup on Saturday - and Benitez was delighted to land the striker.

"I don't know how long (he will play) but I think that he has to play because he is training well, he is fine, but we'll have to manage it at the time," the Spaniard said.

"He's a great player and it was an easy decision for me (to sign him), I told the chairman that I liked the player, so the technical director and the chairman, they were quick and after we signed the player (I was) really pleased because he is a top class player."

Benitez also said he was surprised to be able to land Pepe Reina in a loan deal from Liverpool but was thrilled to acquire his services.

"Obviously, I know the situation and I was surprised, because we were trying to sign Julio Cesar," he continued.

"It was a surprise for us when Pepe Reina was available, so for us it's a big boost, really important because he's a great player."