A 4-2 humbling on their return to the European circuit at Old Trafford on Matchday 1 of the campaign left some questioning whether Sami Hyypia's young charges would be up to the task, but fast forward six weeks and all the signs suggest Leverkusen are going to be knocking around in the competition a while longer yet.
After losing in Manchester, die Werkself bounced back on home soil with victory over Spanish outfit Real Sociedad de Fútbol, before seeing off FC Shakhtar Donetsk two weeks later. On Tuesday, they walked away from the Donbass Arena with a priceless point to maintain their two-point cushion on the third-place Ukrainians and set up what looks like being a down-to-the-wire race for a place in the last 16.
That they were able to deliver such a mature performance in such intimidating surroundings is all the more remarkable, especially given their dismal display last weekend at Eintracht Braunschweig. Falling to their second league defeat of the campaign, the Rhineland club now have four points to make up on Bundesliga leaders FC Bayern München and three on second-place Borussia Dortmund.
Win or bust
Over the course of the next month, Leverkusen face Hamburger SV, Hertha Berlin, 1. FC Nürnberg and Dortmund. Ten days before their top-three clash at the Signal Iduna Park, Leverkusen are also in action in the Champions League. Should they lose to Manchester United and Shakhtar beat Sociedad, Leverkusen will have to take at least a point from their final group game in Spain just three days after facing Dortmund. Even victory might not be enough, depending on the outcome of Shakhtar's trip to Manchester.
Yet if we take a moment to consider the context of Tuesday's draw in Donetsk, it is arguably far too early to be casting aspersions. More often than not, Bayer's Vizemeister reputation precedes them. Few would have tipped Hyypia, in his first season as head coach, to have built a team capable of mixing it with the very best that the Bundesliga and Europe have to offer, but a third of the way into the campaign, they are doing exactly that. Write them off at your peril.
See how Stefan Kießling's phantom goal helped Leverkusen to victory back on Matchday 10, courtesy of the official YouTube channel: