Russian outlet Soviet Sport claims that members of the Reds’ scouting department were in attendance as Azmoun’s Zenit St Petersburg faced Lokomotiv Moscow at the VTB Arena in Moscow.
Reigning champions Zenit were defeated 3-2 but Azmoun scored two goals either side of half-time.
The 24-year-old only joined the Gazprom-owned outfit back in February for a fee of around £10.5million, having neared a loan move to Wolves in January which fell through on deadline day.
Iran international Azmoun, formerly nicknamed ‘The Iranian Messi’, has long been tipped for a move to Europe with Liverpool credited with interest in the player since 2016.