Barnack beat Deeping by one run in tense tussle
Burghley Sixes holders Oundle made an emphatic start to their title defence on the opening night of this year's competition.
They defeated Empingham by 44 runs after a power-packed batting performance.
Mark Hodgson hit an unbeaten 54 while Connor Craig cracked 41 as Oundle raced to 109-1 off their five overs.
Empingham's reply began disastrously after they suffered two run outs in the opening over.
However, Tom Cooper steadied the Rutlanders' ship with an unbeaten 44 as Empingham finished on 65-3.
The most exciting finish of the first night saw Barnack beat Market Deeping by one run.
Worcestershire's Pat Brown was back in Deeping colours for one night and he helped restrict Barnack to 74-4 by claiming a wicket from his over.
Sachithra Perera, who was named player of the night, also blunted the Barnack reply with two wickets in two balls from his over which went for just two runs.
Dan George was the mainstay of the Deeping reply as he raced to 44 as the Outgang Road side reached 57-1 going into the final over.
With Brown on strike, he smashed the first two balls to the boundary but, needing 10 runs off the final four, George was run out for 45 on the final delivery as Deeping fell one short.
Hosts Burghley Park became the final side to secure a quarter-final spot from opening night as they defeated Ketton Sports by 21 runs.
George Holmes hit an unbeaten 24 as Burghley posted 95-3 from their five overs.
Sports got off to a flying start in their reply as Ben Slack's opening over went for 21 runs, including 14 extras.
However, Burghley regained control of proceedings and, despite 28 from Joash Mathys, Sports fell well short.
Tonight's matches see Nassington take on Bourne, Uppingham play Market Overton and Castor clash with Oakham.