Dortmund beating Leverkusen was a step ahead of them ending top 4 in the league left with 1 match to determine where they end up. If Dortmund can successfully win Holstein Kiel in the last game of this season what they wish for is SC Freiburg to lose or draw, SC Freiburg will be playing against Eintracht Frankfurt who are 3rd place also competing in this final game to qualify for Champions League, they can't go easy on SC Freiburg, that last game will determine for this three teams who makes it out of the leading top 4.
Few weeks back Dortmund was sitting in 10th position but now they are fighting for top 4 what a surprise. No one expected them to improve in this manner, they really surprised everyone, they improve their game and made sure they didn't drop anymore points and that is why they were able to get so close. Their top 4 hope could have shattered if they had lost against Bayern Leverkusen but the win actually kept it alive. They just have to win their game and hope Freiburg drops point. They started poorly and ending it well even though they didn't challenge much at least this development is something for them and it might help them have a better performance next season.
Obviously they did incredibly well to try to catching up with the contender of the top 4 position, and their last game on Saturday will be a desicive match between them, Freiburg and Eintracht Frankfurt, the points difference between the occupants of 3rd ,4th and 5th position is 57, 55 and 54 respectively, because there's a game between Freiburg and Eintracht Frankfurt the outcome of these game will decide who qualifies for next season's Champions League competition.