Real Madrid star Cristiano Ronaldo has warned his side to be wary of Bayern Munich’s attacking threat as the Spanish giants attempt to reach the Champions League final.

Real Madrid v Bayern Munich preview: Ronaldo wary of Germans' fab four

Madrid suffered a 2-1 defeat at the Allianz Arena in last week’s semi-final first leg, with Mario Gomez netting a late winner after Mesut Ozil had cancelled out Franck Ribery’s opener for the hosts.

Ozil’s goal means that a 1-0 win at the Bernabeu on Wednesday will be good enough for Real –  but Ronaldo knows bottling up the Germans’ strike-force will not be easy.

Asked which members of the Bayern side worry him most, Ronaldo told the website: “The players who play up front.

“Gomez is one of the leading goalscorers in the Champions League, and Ribery and (Arjen) Robben are also very dangerous.

“They are very good up front – and at the back as well – but we have to be focused on the four in attack, because it is one of them who will make the difference.”

Nevertheless, the Portugal international is confident it will be Real – who are seeking a record 10th European Cup triumph – progressing through to next month’s final, which is ironically being staged in Munich.

“We are well,” added Ronaldo. “I’m sure that, at home, we are going to win, because we are playing in our stadium, in front of our own fans and we have everything we need to be able to win.

“It’s going to be a very difficult game, but I’m hopeful of a Madrid win. They played at home and won, but we got a goal there, which is also important.

“We know that Bayern, after the first leg, are to going to play on the counter-attack, but we also believe they are going to have a lot of respect for us because we are playing at home.

“I hope we reach the final because it is very important to us players, to Real Madrid and to our fans throughout the world.”

Ronaldo, the world’s most expensive player, called on his side’s supporters to play their part on Wednesday night.

“The crowd has to play the most important role as soon as we step onto the pitch, because we can feel it,” said the former Manchester United star.

“If we stand united, things will turn out well.

“It is a decisive match and the players are more confident and feel we can do even better when we feel the backing of our supporters.”

Meanwhile, Bayern coach Jupp Heynckes is preparing for a “battle of the giants” at the Bernabeu.

While a 0-0 draw would suffice for the visitors to reach the final in their own stadium, few expect the clash to end goalless – including Heynckes.

“Tomorrow is going to be spectacular. It is going to be a real treat with everything which belongs in such a football game,” he said.

“Just a fortnight ago, people were saying that Barcelona are the be all and end all, but now Real have gone and won in Barcelona.

“It will be a battle of the giants. Both clubs have a great history and I am looking forward to it, and I hope it has a positive outcome for us.

“We are capable of scoring at the Bernabeu. At the same time, we have shown that we don’t concede many.

“The first-leg result gives us a small advantage, but Real have amazing goalscoring potential and have scored nearly 150 goals so we will be prepared for that.”

Bayern star Bastian Schweinsteiger says the best way to win will be to try to frustrate Real and their fans.

“Of course the stadium has an influence on the game and we are going to have to be particularly careful in the first 20 minutes,” he said. “If the fans then start to see that we are resisting, then I am sure it will quieten down a bit.”

Seven Bayern players are one yellow card away from missing a potential final.

David Alaba, Philipp Lahm, Thomas Muller, Toni Kroos, Luiz Gustavo, Holger Badstuber and Jerome Boateng risk suffering the same fate as Franck Ribery two years ago if they pick up a caution tomorrow, but Schweinsteiger insists holding back is not an option.

“Sure, we have got to ensure we don’t get involved in any scuffles, but you can’t really influence that now,” he said. “We have got to get to the final in the first place, so I don’t think that will actually be an issue.”

Heynckes will not be telling any of his players to take it easy tomorrow night either as he demands total commitment for the crucial encounter.

“You can also go into the tackle without getting a yellow card,” he said. “I will be making that clear to my players.

“But then again, you can never rule out getting a yellow card which is undeserved, like David Alaba did.”

Alaba should start anyway, as should Schweinsteiger, although Heynckes would not confirm the latter’s inclusion in the starting XI, despite him playing through Bayern’s last two league matches and showing signs of having made a full recovery from a troublesome ankle injury.

“Our final training session should give me more of an idea about his condition,” Heynckes said. “I will decide then whether he can start.”

Robben, Ribery, Boateng, Badstuber, Gomez and Lahm should all return after being rested in Saturday’s 2-1 win over Werder Bremen.