A dramatic finale saw Olney take the lead and Leicester Forest miss a late penalty in an 20-18 win.
After falling a try behind, James Hawken converted his own score to make it 8-7 to Forest at half time.
He repeated the feat in the second half to put Olney 14-8 up, and kicked a penalty to make it 17-8.
But back came the home side with another try to make it 17-15, before they kicked a penalty to take the lead at 18-17 in the final minute.
Determined, Olney won a penalty of their own and under pressure, Hawken showed no nerves to kick Olney into the lead.
Unable to get the ball out of play for the final whistle, Olney were penalised to give Forest a chance to win it at the death.
But their penalty was wide of the mark, allowing Olney to hold on for a 20-18 win.