With group leaders Esperance already through to the last four, USMA, who made a disastrous start in Group B with two defeats, appear best placed to join them.
Esperance have 10 points, USMA
six, AS Aviacao of Angola four and three-time champions Canon three with four of the six rounds complete.
If USMA win at home to Aviacao on 3 October and Canon fail to collect maximum points when they host Esperance 48 hours later, the Algerians will advance to the semi-finals.
After a 3-0 hammering in Algiers two weeks ago, Canon were expected to make home advantage pay on Sunday.
But a mixture of wild shooting, bad luck and heroic USMA defending left them with little chance of qualifying for the knock-out phase.
