Osimhen scored for Napoli in his first appearance since returning from the Africa Cup of Nations to help his side to a 1-1 draw against Barcelona in the first leg of their Champions League last-16 tie at the Stadio Diego Armando Maradona.
After a goalless first half, where the hosts failed to have a shot, Lewandowski broke the deadlock in the 60th minute with a drilled strike into the bottom-left corner.
However, the Blaugrana couldn’t build on their lead, with Napoli scoring with their only shot on target.
Osimhen used his strength to roll past Martinez before slotting his effort into the bottom-left corner.
Gundogan went close in the final seconds for Barcelona, but he curled his low effort just wide of the left post.
It was a disappointing display from Napoli, but they still created more than Barcelona.
The teams will face off again with everything to play for midway through March.
Napoli will now return to Serie A action, with Calzona’s men travelling to Cagliari for his first league match in charge.
As for Barcelona, they host Getafe in LaLiga.