MUNICH: Real Madrid coach Zinedine Zidane warned on Tuesday Bayern Munich are better than they were last season when the Spaniards beat them en route to the Champions League title.

Bayern, five-time European Cup winners, host 12-time champions Real in a mouth-watering semi-final first leg on Wednesday.

The Spaniards have won back-to-back titles but the treble-chasing Bavarians are in sensational form ever since manager Jupp Heynckes took over from Carlo Ancelotti in October.

Bayern have already secured the Bundesliga title and have reached the German Cup final as well.

"They have been transformed under him," Zidane said of the 72-year-old Heynckes. "I have maximum respect for him. He has done big things. It is remarkable."

Heynckes is on a record 12-game winning run in the Champions League stretching back to 2013 when he won the title with Bayern before retiring. He will leave the club again at the end of the season.

"We will need a big performance against a strong opponent. Bayern are a great club with great team spirit," Zidane said, adding last season's victory in the quarter-finals over the Germans meant nothing now.

"I don't think there are any favourites. It is a semi-final and it is completely different to last season. It is a different match, we cannot compare the two," the Frenchman said.

He may have become the first coach to lead a team to consecutive Champions League crowns but Zidane knows he must win it a third time in order to salvage what will otherwise be regarded as a disappointing season for the La Liga side with no silverware.

"In the league, you have to be consistent every three days and we weren't at the start of the season and that's the difficulty we have," he said.

"I have no doubts that mentally we will be at 150 percent tomorrow."