Enyimba's Gbenga Ogunbote believes complacency cost them a spot in the second round of the Federation Cup.
The People's Elephants were ousted from the competition by ABS after they were condemned to a 2-1 loss on Wednesday.
Prior to the encounter they had defeated the Saraki Boys 3-0 in Sunday's Nigerian topflight encounter.
“I already forewarned my players that they must be ready to play a fresh match and not focus their minds on the result between both teams some days earlier,' Ogunbote told Goal.
"We didn’t respect our opponents and we allowed complacency to set in," he continued.
"We have lot of work to do before the match with Rivers United this weekend.
“It was a pity that we couldn’t explore the possibility of qualifying for the continent through the FA Cup but we have to continue pushing for it till the end of the season in the league with the chance to get in the FA Cup all but gone with our exit.
On weekend's Nigeria Professional Football League fixture against Rivers United, Ogunbote says: “Rivers United are no pushovers and even though they are struggling in the league this season they will still want to come all out and face us so as to move closer to confirming their stay in the premier league next season.
"We can’t afford to lose in Port Harcourt and it is my duty to let my players aware of this,” he concluded.