"It's comparable to the final three years ago between Manchester United and Chelsea where everybody thought 'oh the English are so strong now they will dominate the Champions League for years to come' and it didn't happen," Lehmann told BBC Radio 5 Live's Sportsweek programme.
"I think these two teams who we have seen are the cream of German football. Then you look at the last table, the German Bundesliga, you see the gap between the top two teams and the other teams in terms of points is huge.
"You can't put this quality on to the whole league in Germany.
"It's very hard to play Wigan away for a team like Manchester (United) - it's not given that you will win that game whereas in Germany when Bayern Munich play teams from the bottom of the league you know that they're going to win."