Ahmed Khaldi claimed his fourth goal of the second-tier African competition by slamming a 98th-minute spot kick over goalkeeper Mahdi Soliman into the roof of the net.

Just a few minutes earlier Zamalek thought they had taken the lead through substitute Juan Bezerra in front of a sell-out 50,000 crowd at the July 5 Stadium in Algiers.

The Brazilian took advantage of a miskick in midfield by Hocine Dehiri to race through and fire a low shot wide of goalkeeper Oussama Benbot.

However, as the Cairo club celebrated what they believed was the match winner, VAR officials informed the Mauritanian referee of an incident that preceded the goal.

Big screen replays showed Zamalek centre-back Hossam Abdelmaguid fouling USM substitute Rayane Mahrouz, striking the Algerian in the back with his knee, and handling the ball inside the area.

After reviewing the incident at the pitch-side monitor, the match official cancelled the Zamalek goal and awarded USM a penalty instead.

Khaldi held his nerve amid lengthy, heated protests from Zamalek before giving Soliman no chance with a superbly struck penalty.

As the final whistle sounded following 11 minutes of added time, Zamalek felt hard done by as they also had the ball in the net midway through the second half.

On that occasion there was no time for celebrations as the referee swiftly judged that Angola-born Zamalek winger Chico Banza had fouled USM defender and Cameroon international Che Malone.

Livewire Banza had a chance to break the deadlock early in the second half when he lobbed the ball over Benbot only for his goal-bound poke to be cleared by Dehiri.

The return match is set for May 16 at the Cairo International Stadium with Zamalek seeking a third Confederation Cup title and USM a second.

A record first prize of $4 million is on the line with the runners-up receiving $2 million in the African equivalent of the UEFA Europa League.

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