Very curious to see what Leverkusen will do against Union today. Will they be able to win and get back 1st position from Bayern ? Or they will choke and lose points against Union Berlin ? because frankly , Union is in a desperate situation in Bundesliga with 5 defeats in a row , 17th place that will automatically relegate them at the end of the season so I do expect them to actually put up a fight against Leverkusen today or the rest of the season will be a disaster for them.. . Last year Berlin already lost one team and it would be a shame if they will remain without any football clubs in first division by next year. 
Leverkusen should win this game to take the top back from Bayern. if they Drop points this time, that will affect their mentality remembering that it's not easy to compete with bayern from behind. Xabi Alonso should prepared his team to face Berlin who are in fighting spirit to gain positive result after negative trend they experienced so far.
I think Alonso knows that it's not easy to fight that kind of team. His team cant relax while seeing Bayern taking the lead on the table. Berlin are actually a bad team, but they are just in a very bad form right now. but I think Leverkusen will be well-prepared and win the game.