Abbas Amidu scored twice as CAPS United of Zimbabwe stunned Zamalek of Egypt with a 3-1 victory in Harare on Sunday, as the penultimate round of African Champions League group matches continued.
Ronald Pfumbidzai put the hosts ahead in a Group B match they had to win to keep alive their hopes of qualification for the quarter-finals.
Nigerian Stanley Ohawuchi levelled against the run of play before half-time for five-time African champions Zamalek.
After the Egyptian club had a goal controversially disallowed for offside, Amidu put the Zimbabweans ahead again on 75 minutes and added a third in stoppage time.
CAPS are away to leaders USM Alger of Algeria next Sunday in the final series of group fixtures and must win to finish in the top two and make the last eight of the elite African club competition.
Zamalek must also win at home against Al Ahly Tripoli, if they are to avoid a shock elimination.
USM and Ahly Tripoli - who drew 1-1 on Friday night - have eight points, CAPS six and Zamalek five in one of the most competitive of the four groups.
A weak clearance by the Egyptian "White Knights" offered Pfumbidzai the chance to fire past goalkeeper Ahmed El Shenawy for the opening goal on 31 minutes.
Zamalek levelled off a counter-attack with goalkeeper Prosper Chigumba parrying a shot from Ohawuchi, but he was not able to prevent it looping into the net.
Amidu collected a Ronald Chitiyo pass and fired home to put CAPS ahead again and then raced from his own half with the ball before shooting past El Shenawy on 94 minutes.
Zamalek last won the Champions League in 2002 while CAPS are competing in the group stage for the first time.
The Zimbabweans pulled off the biggest shock of the qualifying rounds this season by eliminating five-time African champions TP Mazembe from the Democratic Republic of Congo.