The 35-year-old has enjoyed spells with both clubs during his career, conquering Europe with Barcelona in 2006.

He believes that, despite the quality Real Madrid and Borussia Dortmund possess, the other two are the strongest out of the four sides.

"Many are saying that Bayern are slight favourites, but I see things differently. The team that Lionel Messi plays for is never an outsider, and both teams are equally strong," van Bommel told El Mundo Deportivo.

"Bayern Munich and Barcelona are the two best teams in Europe and I am sure that the winner of this tie will win the Champions League."

When asked which side he wanted to progress from their semi-final, van Bommel insisted he did not have a preference.

"I'm neutral. I have played for both clubs, and I had a great time at both, even though I was at Bayern significantly longer," he said.

"I am sure that we will see two special games."