A spirited second half performance saw Merreikh score thrice courtesy a brace from in-form Bakri Al Medina and the other by Amir Kamal Suliman. Earlier, Younes Kadri and Abdelmalek Abbes shot the Algerian debutants into a two-goal lead at half time.
With their place at the last four secured 24-hours earlier after USM Alger crushed holders ES Setif 3-0 in Algiers, Merreikh never looked back and put up with a fine display to deny Eulma their first point at the pool stage.
The homers got off well and deservingly went up on the quarter-hour mark through Kadri who shot past goalie Salim Omar in a one-on-one situation.
On 26 minutes, Abbes doubled the lead with a superb chip past onrushing Omar for a two-goal lead at the interval.
The visitors were undaunted by the two-goal deficit and never looked back, with consistent raids into the half of their hosts. The introduction of Ghana-born midfielder Francis Coffie for Sharafeldin Ali upon resumption marked the turning point of the game for the Omdurman-based club.
Suliman reduced the deficit by heading home from a Coffie cross on 67 minutes before Al Medina drew level four minutes later with a sublime finish from close range.
In stoppage time, Eulma defender Adel Namane fouled Ivorian Didier Lebri in the vital area for a penalty which Al Medina converted with ease to secure his side the maximum points.
23.08.2015 20H00 El Hilal (Sudan) vs TP Mazembe (DR Congo)
23.08.2015 20H30 Moghreb Tetouan (Morocco) vs Smouha (Egypt)
21.08.2015 20H30 USM Alger (Algeria) 3-0 ES Setif (Algeria)
22.08.2015 20H30 MC Eulma (Algeria) 2-3 El Merreikh (Sudan)
*All times are in local time