Napoli's Nigeria striker Victor Osimhen got on the scoresheet again as the Serie A leaders beat Eintracht Frankfurt 2-0 in their Champions League last 16, first leg on Tuesday.

Osimhen scored before the break as Giovanni Di Lorenzo doubled their lead after the interval before the second leg in southern Italy on March 15.

Having scored in each of his last seven league matches, Osimhen gave the visitors the lead after 39 minutes, finishing off a swift counter just after Frankfurt keeper Kevin Trapp saved a Napoli penalty.

Frankfurt were reduced to ten men early in the second half after a nasty challenge from striker Randal Kolo Muani found the shin of Napoli's Frank Anguissa.

The visitors doubled their lead soon afterwards when Khvicha Kvaratskhelia set up Giovanni Di Lorenzo with a superb back heel -- putting Napoli on course for what would be their first ever Champions League quarter final appearance.

Buoyed on by a home crowd celebrating the club's first venture into the Champions League knockout rounds, Frankfurt started stronger, with in-form striker Randal Kolo Muani creating a goal chance out of nothing after four minutes.

With his back to goal inside the Napoli penalty area, the France forward chipped the ball over his head, turning to fire just wide of the right upright.

But as the opening half wore on the visitors' quality began to show, with the runaway Serie A leaders dominating possession and field position.

The win sees Napoli return to Naples for the return leg in a dominant position as the 1988-89 Europa League winners look to go past the last 16 for the first time in their history.

The current Europa League holders Frankfurt will likely see their first Champions League campaign come to an end at the  Diego Armando Maradona Stadium in March, unless they can turn the tie dramatically in their own favour.