AmaZulu suffered their second defeat in the CAF Champions League group stages after going down 2-0 to ES Setif on Saturday night.
There were no less than four new changes from Usuthu, as Thembela Sikhakhane, Keagan Buchanan, Luvuyo Memela and Siphelele Mthembu were recalled after the loss to SuperSport United.
Setif made a fast start on 11 minutes when Riad Benayad attained possession and went on to beat goalkeeper Veli Mothwa with a smart strike from the edge of the area.
Usuthu were under the cosh just before the half-hour mark and needed a firm point-blank save from Mothwa to prevent Benayad from completing his brace off a close-range attempt.
Despite the slow start, AmaZulu sprung to life in the closing periods of the first half and threatened through a looping attempt off a free-kick from close-range by Memela.
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AmaZulu's hopes of a comeback got tougher when Mothwa's failure to collect a free-kick prompted Akram Djahnit to take hold and slot into the net with the last kick of the first half.
Entries from the Usuthu dugout ahead of the second half saw Bonginkosi Ntuli introduced for Mthembu and Ceesay sacrificed in place of Andre de Jong.
Those arrivals urged Usuthu ten minutes in and they could’ve reduced the lead from a cutback off a free-kick, but Ntuli battered the woodwork while De Jong was stopped from burying home the loose ball.
AmaZulu didn’t stop causing the host problems moments thereafter, as a first-time strike way outside the area from De Jong shaved the top of the crossbar.
In th end, Setif were able to see out the latter stages of the second half to secure maximum points and leapfrog Usuthu into second spot.
AmaZulu: Mothwa, Gumede, Sikhakhane, Xoki, Malepe, Memela, Buchanan, Makhaula, Ceesay, Mthembu, Mulenga.
Subs: Amonome, Masilela, Majok, Ntuli, Shange, Mlambo, Ekstein, Khumalo, De Jong.