Laois lie in wait for Enda Mulhare's charges while Westmeath will take on Kildare in the next round.
Just hours after victory in the Joe McDonagh Cup contest between the two counties, Offaly's minor hurlers maintained their 100% start to their championship campaign after beating Westmeath on Saturday.
The Faithful County secured top spot of group one in tier two after a 2-15 to 1-13 win.
In a closely fought contest, the counties were tied at the break at 8 points each.
It was goals that decided the contest with all three coming in a five minute period.
Killian Wynne hit the back of the net first in the 38th minute for Offaly, Cormac McKeogh struck back moments later for Westmeath only for Conor Egan to fire Enda Mulhare's side back into the lead.
Offaly will now face Laois in a preliminary quarter final on Saturday with Westmeath facing Kildare.
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