Clashes also broke out Thursday night when a Europa League match between Ajax and Maccabi Tel Aviv took place.
Meanwhile, Ajax’s former player, Hedwiges Maduro, will take charge as the caretaker manager until a permanent replacement is announced.
Meanwhile, the former Sevilla player is eligible to appeal the judgement but it is still unclear if he will return to his home country to serve his sentence.
The match was first halted after seven minutes when smoke bombs were thrown onto the pitch from a stand with Groningen fans.
The signs are ominous as they struggle to build a new team in the wake of record sales last year.
Osimhen scored just six minutes before the final whistle to seal the victory for Napoli at the Diego Armando Maradona Stadium.
The victory sent Napoli top of Group A with a 100 per cent record and 11 goals difference.
Liverpool defeated Ajax 2-1 at Anfield to record their first victory in the competition.
Super Eagles stars Calvin Bassey, and Victor Osimhen will put their national affiliation aside to hustle for club glory.
Bassey has signed for Ajax in a lucrative five-year deal that makes his transfer the largest for Rangers in terms of transfer fee (£22.7).
