Osimhen scored as Napoli beat 18th place Sampdoria 2-0 in their Serie A clash at the Luigi Ferrari Stadium.
The red-hot Super Eagles forward netted the first goal for table-topping Napoli in the 19th minute before a penalty by Elmas doubled the scoreline in the 82nd minute.
Sampdoria not only suffered a defeat but had to play with a man down for most parts of the game as Rincon was sent off 38 minutes into the match.
Osimhen had one goal and five shots in the Serie A game.
The win means Napoli who remain in the top spot with 44 points are seven points clear of second-placed Juventus while Sampdoria sit in 18th place with only nine points accrued so far in the season.