The German visitors were arguably the stronger side in the Champions League playoff first leg, but the substitute's second-half strike gave the Italians the advantage.
Balde Keita came off the bench to fire Lazio to a fortuitous 1-0 victory over Bayer Leverkusen in Tuesday's Champions League playoff.
Stefano Pioli's men were pressed relentlessly by the German visitors in the first leg at the Stadio Olimpico, who went from strength to strength as the match fizzled by with exciting pace.
Minutes after Hakan Calhanoglu was denied a goal with a brave - but controversial - offside decision, Lazio pounced against the run of play late in the second half via Keita's pace and precision finish.