Madrid arrive in the Bavarian capital holding a 1-0 lead thanks to Karim Benzemas 19th-minute goal in last Wednesdays first leg in Madrid and are looking to avenge their defeat at the same stage to Bayern two years ago.
History is on the Germans side.
Bayern have never lost to Real in Munich, with eight victories and one draw, to lead the overall series with 11 victories to Madrids eight from 21 encounters.
The second-leg is finely poised.
Real maintained their positive momentum since beating Barcelona in the Copa del Rey final before their first-leg victory over Bayern by romping to a 4-0 win over Osasuna in the Spanish league on Saturday. Ballon dOr winner Cristiano Ronaldo proved he is fit for the Munich clash after a hamstring injury by scoring twice to leave him on 47 goals in all competitions for the season.
Real coach Carlo Ancelotti rested stars Benzema, who picked up a knee knock in the first leg, and Gareth Bale, who was recovering from flu, at Osasuna. The Italian has insisted both men should be fit to start at the Allianz Arena.
I am sure that whatever eleven I play will be full of desire and excited to play such a big game, said Ancelotti. Everyone should be calm because we are going to prepare properly. The objective is to score, not to defend, and that is the manner in which we will continue to work.
FIRST STRIKE CRUCIAL
Ancelotti has never lost to a German team in six encounters from his time as AC Milan manager, but the key to Tuesdays game will be who scores first.
Real will be chasing the first goal in Munich which would leave Bayern needing to score at least three times to progress to their fourth Champions League final in five years. Worryingly for coach Pep Guardiola, Bayern have conceded the first goal in seven of their last nine matches since winning the Bundesliga title with a record seven matches to spare last month.
A woeful first-half in Saturdays dress rehearsal saw the hosts 2-1 down to Werder Bremen in Munich before Bayern roared back with four second-half goals to claim a comfortable Bundesliga win. But the flattering scoreline failed to mask Bayerns dreadful defending in the first 45 minutes, which Guardiola admitted gave him cause for concern.
That is the first time that I have been a bit disappointed and sad about the first half the fans didnt deserve that, said Guardiola. We were better in the second half thats good for the mood ahead of the Madrid match but it will be a completely different game. I trust my team and I hope that we can all manage it together.
Bayern are bidding to become the first side to retain the Champions League trophy and will be the first team since Juventus (1996-98) to reach three consecutive finals if they get past Madrid to reach the final in Lisbon on May 24.
In contrast, Real are eager to reach their first Champions League final since winning the title in 2002 having bowed out at the semi-final stage for the last three seasons running.
With Ronaldo and Bale both fit, Ancelotti is set to include both in his forward line alongside Benzema with Isco sitting on the bench.
Guardiola has some key selection decisions to make after Brazils Rafinha struggled with the fleet-footed Real attack in Madrid and one option would be to move captain Philipp Lahm to right-back from the defensive midfield.
Guardiola must also decide which stars to use in the attacking midfield after Germany pair Thomas Mueller and Mario Goetze both started on the bench in Madrid, with Mueller in particular voicing his discontent.
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