Negotiations are now ongoing regarding the Iran international, who is one of two or three options being explored as OM aim to bring in a new striker on deadline day.
Les Phocéens are in need of a forward following the departures of out-of-favour s Luistrikers Suárez (25) to Almería and Bamba Dieng (22) to Lorient.
According to L’Equipe, Azmoun has already given his green light to join the club. Talks are ongoing with the Bundesliga’s ninth-placed side over a deal whose transfer fee falls below the €10m mark.
Azmoun joined Leverkusen from Russian outfit Zenit St Petersburg one year ago. This season, the 68-cap Iranian international failed to find the net with the Xabi Alonso-led side.