First match are always important becauyot will give the players believe that they can do vey well in the season and form the four match that you have listed, here's my prediction on who I think the matches are going to end.
1. Borussia Mönchengladbach - Leverkusen: Leverkusen wins
2. Freiburg - Vfb Stuttgart: This is going to end in a goalless draw.
3. Borussia Dortmund - Frankfurt: Dortmund wins
4. Wolfsburg - Bayern Munich: Bayern Munich wins with more than 2 goals margin.
It will be a wrong move to bet against Bayern Munich that they are going to lose or draw at the start of the season. When the season has gone into some game week and the champions league starts, then you can have doubts about teams like Bayern Munich winning. Their league games will be draws or losing because they will be playing too many games by then and the players would be tired.
First matches are always exciting, always a lot to be found out in those matches. Everyone is looking forward to those matches, every player has a lot to prove, a lot to show the manager.
In all four of these matches, there are certain areas of battle. These are surprisingly good matchups, rare for the first gameweek. I think Mönchengladbach always starts as a promising team, and they've beaten Bayern a couple of times, and drawn them. Leverkusen, after a flying season, will face a good challenge after being back. Stuttgart and Freiburg is an equal game, Dortmund vs Frankfurt will be very exciting, and Bayern has a lot to show under Kompany. Let's find out!