The ex-Germany international believes that the Bavarians are capable of competing with the best, but is of the opinion that they face a difficult match against Los Blancos
The 67-year-old is of the opinion that the Blancos and the Bavarians have equal chances of progressing to the showpiece at the Allianz Arena, branding the slender advantage of Jupp Heynckes' men before the return "a bit of momentum".
Netzer believes that Real Madrid will be firing on all cylinders at the Santiago Bernabeu, and will be much more aggressive than in the first leg.
"It will be a different Real from the one we saw in the first leg. They will be more offensive and scoring opportunities will come.
"They [Bayern] must not try to save the result. This is 100 per cent wrong. They still have to attack and let scoring opportunities play themselves out.
"For me it [the semi-final] remains 50:50. It's nice that they won [the first leg], which gives a bit of momentum - but nothing more.
"Bayern must, above all, be smart and play to their strengths. [Arjen] Robben and [Franck] Ribery are needed, they must lead the team."
The second leg at the Bernabeu kicks off at 20.45CET on Wednesday evening.
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