In Tunisia, trouble erupted before the kickoff at the 60,000-seat national stadium in Rades near Tunis when more than the 5,000 spectators permitted under coronavirus protocols gained entry.
Police responded to taunts from an unruly crowd by firing tear gas and stun grenades as both squads abandoned warming-up on the pitch and fled to the changerooms with some coughing and others gasping for breath.
Amid fears that the clash of the north African giants would be called off, order was restored and Ahly agreed to play after a one-hour delay having received a written pledge guaranteeing their safety.
It was the seventh time the Egyptian Red Devils have beaten the Tunisian Blood and Gold in 19 meetings in the marquee African club competition with eight drawn.
Ahly host the return match in Cairo next Saturday and a draw will suffice to secure a place in the July 17 final in Moroccan economic hub Casablanca.
While Ahly winning was not unexpected, first-time semi-finalists Chiefs succeeding certainly was with vastly more experienced Wydad hot pre-match favourites to build an aggregate lead.
Nurkovic was flagged offside by an assistant referee after beating goalkeeper Ahmed Tagnaouti with a shot into the corner of the net.
But a VAR review delivered a different outcome and the Senegalese referee awarded the goal.