Florian Wirtz scored the only goal of the 1-0 victory deep in first-half injury time after Robin Gosens was shown a red card.

Union succeeded in keeping it to one but, with Bayern Munich losing again, it was enough to move Xabi Alonso’s side 16 points clear at the top of the table with six games remaining.

Frederik Ronnow had made fine saves from Borja Iglesias and Alex Grimaldo before the game burst into life in first-half injury time.

First Gosens, who had been booked early on, was shown a second yellow card for a foul just outside the box.

The resulting free-kick caused chaos in the Berlin penalty area and, after a VAR check, the referee ruled Christopher Trimmel had handled and pointed to the sport, with Wirtz making no mistake.

Leverkusen had the majority of the play in the second half as they sought a second but Ronnow refused to be beaten again, saving impressively from Nathan Tella and Iglesias.