Frank Lampard has backed Chelsea star Raheem Sterling to prove he is still one of the world's best against Real Madrid. 

The England forward has struggled since his £47.5million switch from Manchester City to Stamford Bridge. 

Lampard recalled Sterling in his first game back in charge as caretaker boss but he could not stop the Blues slipping to a 1-0 defeat at Wolves on Saturday as their disappointing Premier League campaign continued. 

Sterling, 28, has scored just seven goals this term but netted the crucial opener in Chelsea's 2-1 aggregate win over Borussia Dortmund in the last 16 of the Champions League last month. 

They go to Real Madrid on Wednesday for the first leg of their quarter-final and Lampard expects the former Liverpool man to step up again. 

He said: "Raheem has been there and done it and there's history of producing. I think he's a fantastic player. 

"He's been one of the best wingers in the world for a long time. At times, maybe in some people's opinion, the best. 

"He's risen to games like that before so that's something we'll obviously rely on because some elements of the squad are maybe a bit younger. 

"He's certainly a player of a high level and understanding of the game that it won't faze him. 

"He's a top player. Raheem has shown what a player he is."

Lampard, 44, lifted the Champions League with Chelsea in 2012 when they finished sixth during an underwhelming league season, with Roberto Di Matteo replacing Andre Villas-Boas late in the campaign. 

But after Matheus Nunes' sunk the Blues at Molineux, he admitted there is no secret to producing in Europe.

Lamps added: "There's a lot to it. Part of that [2012 success] was we parked the bus at the Nou Camp and managed to hang on for our dear lives! 

"But we did have a huge desire, a big character and a level of talent in the group that had been striving for years to win a Champions League. 

"A team and a group will always go through tough moments to get to great ones."