The host were by far the better side as they tore apart a hapless Nigeria team who ended the game with ten men after Eneji Moses was given the marching off orders early in the second half.
Left-winger Ismail Haddad was the star of the Moroccans as he had a say in no less than three of the goals.
Morocco unsettled Nigeria with their early dominance as the West Africans laboured in search of their rhythm.
And they kept the Nigerian backline busy till the quarter-hour mark during which El Kaabi was denied by the crossbar from a Hadraf cross from the left.
The Super Eagles came into the fore around the 20th minute mark but rarely threatened the Moroccan defence.
Just before the break, the stadium came alive with the opener courtesy Hadraf.
Captain Badr Benoun went on a solo run beating two players and found Abdeljalil Jbira whose cross was slotted home by Hadraf to send the stadium into raptures.
Trailing by a lone goal, Nigeria’s chances of a comeback were dealt a severe blow two minutes after recess when Moses Eneji was sent off for a second yellow card after fouling Hadraf.
The Atlas Lions made the best of their numerical advantage and it was only a matter of time that the second goal would come.
The second goal came on 61 minutes through El Karti, and yet again Haddad was the architect.
El Kaabi was for the second time denied the post and Haddad pounced on the loose ball and fired a shot a goal that Nigeria goalkeeper Oladele Ajiboye parried for El Karti to head home the rebound.
Hadraf completed his brace two minutes later after Ajiboye made a weak touch of a Haddad cross, and the former tapped home the rebound to take the game beyond the Nigerians.
El Kaabi finally registered his name of the scoring cards, firing past Ajiboye from close range on 74 minutes for his ninth of the competition, and seal victory.
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