Liverpool manager Rafael Benitez has backed Spanish midfielder Antonio Nunez to make an impact at Anfield despite an inconsistent first season in English football.

The 25-year-old joined as part of an exchange deal which took England [Images] striker Michael Owen [Images] in the opposite direction to Real Madrid [Images].

"People have been very critical of him and tried to compare him with other players of the past. But if you were to see the price of the player and compare that with other players then you would know the criticism has been very unjust," Benitez told the Liverpool website.

"Antonio is not at his level yet, he knows that and we know that, but we didn't pay a penny for him. Okay, he's not playing well but he is working very hard to improve and that is the most important thing."

Nunez, one of five Spanish players to have linked up with Benitez with mixed success since the former Valencia coach took charge at Anfield, twisted his left knee in training soon after his move in August.

He had to wait until late November to make his debut -- coming on as a second-half substitute in the 2-1 victory over Arsenal [Images]. Nunez has featured in 15 games this season, has yet to register a goal and was sent off in the FA Cup third round defeat by second division Burnley.

"It has been very difficult for him. If you arrive at a new club in a new country from Real Madrid then you are under pressure," added Benitez.

"Then if you get injured on your first day and are out for three months and then come back into an inconsistent team it is very difficult."

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