A goal in the first-half by Malachi Ohawume and two more from the duo of Wasiu Jimoh and Esor Okwa in the second-half helped the Pride of Rivers to a crucial victory that has seen then move up four places on the NPFL table.
Coach Stanley Eguma and Gbenga Ogunbote both made changes to their squad having after disappointing results in their last outings against Sunshine and Bendel Insurance, respectively.
For Rivers United, Coach Eguma opted for the attacking trio of Bamba Bakary, Kehinde Adedipe and Ossy Martins.
On his part, the Flying Antelopes gaffer settled for the duo of Emeka Ayogueke and Micheal Uchebo to lead the line.
It was the visitors that almost took the lead inside the first five minutes but Kunle Odunlami made a goal-line clearance to save the blushes of the hosts.
After the early scare, Rivers United scare took control of the game but they were unable to fashion any clear cut chances.
Rangers were dealt a big blow just before the half-hour mark as their striker Uchebo sustained an injury and to be replaced by diminutive forward Ajani Ibrahim.
After initially failing to exert themselves, Rivers United finally made their dominance count when Ohawume broke the deadlock in the 36th minute when his gentle chip sailed past the diving Rangers keeper Nana Bonsu.
Both teams maintained the status quo into the second half and it was Rivers United that continued their dominance as they continued to push to extend their lead.
Their sustained pressure paid off in the 57th minute when Jimoh tapped in from close range to double the lead.
The hosts ensured that there was no coming back for Coach Gbenga Ogubote’s men when Okwa Nelson got the third goal for Rivers United; weaving through the Rangers’ defense before slotting the ball into the back of the net.
Thursday’s defeat is Rangers' worst in the league this season but they are still top in Group A of the NPFL with 31 points from 16 games.
Rivers United, meanwhile, have now moved up to fifth spot with 23 points from 16 games.