Stefan Kießling scored the quickest goal of the season after just 40 seconds to put them on the road to victory before prodigy Julian Brandt added a second midway through the first half. Sandro Wagner made things interesting by pulling a goal back before the interval, but Leverkusen held on to a crucial victory in terms of their UEFA Champions League qualification hopes.
Only 40 seconds were on the clock when the ball was whipped in from the right by Giulio Donati and met by a stooping header from Kießling at the near post. It was the quickest goal in the Bundesliga this season, and the best possible start for Lewandowski's men. Gonzalo Castro then almost added to it in the third minute with a volley from the edge of the area, which just missed the target.
Exactly what Lewandowski had done to Leverkusen in his first seven days in charge will remain his secret, but it was clear that their mentality had been transformed. Gone was the bag-of-nerves outfit that had picked up just one win in their last nine games - here was a team showing the confidence garnered from the first half of the season in which they were second only to FC Bayern München.
Brandt at the double
In the 19th minute, Sebastian Boenisch's speculative effort had Thomas Kraft beaten, but not the crossbar, and the woodwork was soon rattling at the other end, as Änis Ben-Hatira leaving Bernd Leno no chance with the visitors' first attempt of the game. It was a key moment as the hosts' second goal followed just moments later.
Brandt showed a confidence and composure that belie his 17 years to lift the ball over Kraft and double Leverkusen's advantage from Heung-Min Son's inch-perfect pass, netting for the second game in a row. Wagner pulled a goal back for the guests as he glanced Tolga Cigerci's free-kick into the bottom right-hand corner, and it was game on going into the second 45 minutes.
Holding on to fourth
Leverkusen began the second period as they had begun the first, but after 15 minutes of probing and with Hertha looking better organised, errors crept into their game. Sami Allagui went close to levelling as the home side's nerves became apparent, although Wagner almost did them a favour when he turned a cross towards his own goal, with Johannes Van den Bergh in the right place to turn the ball behind.
The enterprising Son continued to keep the Hertha defenders on their toes, while Kießling spurned a presentable chance to settle the home fans' anxiety going into the final minutes. There were to be no scares, though, as the hosts ran down the clock with maturity and authority. Lewandowski's men now return to fourth in the standings with four games to go, and a place in the Champions League is now theirs for the taking.
Line-ups and statistics
Relive Stefan Kießling's early goal at the BayArena, courtesy of the official Bundesliga YouTube channel: