Emmanuel Amuneke's lads stepped up their preparations for the forthcoming U-17 African Youth Championship qualifier with a clinical victory over an Umuahia's age grade team
Goals from Promise Orji, Suleiman Abdullahi and Jack Ipalibo were all the Golden Eaglets needed to extend their unbeaten run to 10 games against domestic teams.
Orji broke the deadlock in the 14th minute when he followed up with a shot after Ebere Osinachi's effort rebounded into play.
Chinedu Madueke could have doubled his side's lead almost immediately but his efforts was saved by Lucky Jimoh in goal for Diamond.
On the other end, Amos Benjamin was forced to make a save also from Diamond forward Stanley Kanu as the first half dragged to an end.
On resumption of the second half, both teams brought in fresh legs with Eaglets making seven changes as against four by Diamond yet they both stood neck-to-neck.
Towards the end of the encounter, Abdullahi capitalized on a defensive mishap in the opponent's area to slot home Eaglets' second goal while Ipalibo's shot was deflected into the net for Golden Eaglets' third.
Diamond FC have lost thier previous meetings with the Nigeria U-17 team bowing out 5-1 and 5-0 respectively.