The former West Germany international is confident that his old club can see off Carlo Ancelotti's side in Tuesday's Champions League semi-final
Carlo Ancelotti's men claimed a 1-0 first-leg victory over the Bavarians last week thanks to Karim Benzema's goal to leave the last-four tie delicately poised.
However, Breitner is confident that the European champions will come good in the second leg and knock the Spanish giants out of the competition.
"If we put in a normal performance, whether Real Madrid are at home or in Munich, we can win," the former West Germany international, who played for both clubs, told Sport1.
"That's because we're better. We don't have 11 bullets in the team or Cristiano Ronaldo but we're the better team in the tie.
"But we need to play as we know, as we did in Madrid. We also had Franck Ribery return to form against Bremen. The last half hour was a pleasure.
"This makes me optimistic for Tuesday. We will continue to do what we did in the second half against Bremen."
Guardiola's tactics have come in for criticism in recent weeks after a series of limp performances going forward but Breitner has leapt to the Spaniard's defence.
"How can you criticise Guardiola if we have three or four poor weeks?" he asked.