Leinster Lightning claimed their 5th T20 crown in six seasons with an emphatic 41-run win over the NW Warriors, while Northern Knights beat Munster Reds by 39 runs to move into second.
A superb unbroken fourth wicket partnership of 122 between Lightning captains past and present - John Anderson and George Dockrell - was the launchpad for a Lightning total of 182 for 3.
The pair had come together as the Warriors had held the advantage at the halfway stage with the hosts on 60 for 3 - two wickets for Graham Kennedy (2-20), one of which thanks to an absolutely stunning running catch by Rishi Chopra accounting for Simi Singh. The Coleraine youngster sprinting 30 yards at deep midwicket and diving full length to hold on.
Thereafter the Warriors bowling and fielding disintegrated under the pressure applied by Anderson in particular, with Dockrell an admirable foil.
Anderson unfurled his full repertoire of ramps, sweeps - both conventional and unorthodox - on his way to 76 from just 41 balls (4 fours, 5 sixes), adding 122 in just 62 balls with Dockrell (40*).
The Warriors cause wasn't helped by injuries to Varun Chopra (shoulder) and David Scanlon (back) which forced both to leave the field.
The Warriors chase of 182 started promisingly as William Porterfield (19) and David Rankin added 36 in 27 balls, but once Dockrell dismissed the Irish skipper, the innings stalled.
Rankin (37) and Stuart Thompson (19) added a run-a-ball 28 but by that stage the required rate was well into double figures and the hosts never relinquished their stranglehold on the contest.
Aaron Gillespie sparked briefly in an entertaining 34, but Eddie Richardson's four wicket haul speeded Leinster to the 41 run win - the North County man denied the chance to join Tyrone Kane and Craig Young in the five-wicket club as Chopra and Scanlon's injuries meant they didn't bat.
The Northern Knights won the morning match thanks to a fine all-round display.
They clearly set out to play an aggressive brand of cricket and with openers Ally Shields (24) and Nigel Jones (13) opening stand of 34 in 16 balls, the tone was set.
Adam Dennison (35) and Mark Adair (21) kept the pace going, but with Yaqoob Ali's (2-12) introduction, the innings stalled as the Knights kept losing wickets at crucial junctures.
Indeed, with two wickets apiece for Jeremy Benton, David Delany and Jarred Barnes, their innings was in danger of falling short as they collapsed to 124 for 8.
Peter Eakin's excellent cameo of 25 in 15 balls, with Jacob Mulder also striking a few lusty blows got them up to 165.
The Munster chase got off to a steady start in the power play as Oliver Gunning (26) and Stephen Doheny (24) adding 50, but thereafter the Knights showed their nous and mixed up their pace well.
Leg spinner Jacob Mulder got his mojo back to collect 3 for 18, while Shane Getakate also took three wickets as Munster fell apart under scoreboard pressure - 126 all out.
The Knights catching was exceptional, and the one handed leaping effort on the long-on boundary by Nigel Jones which dismissed Max Sorensen was the defining moment of the game.
Sunday's game ssees the Warriors and Knights battle it out for second place (11am) while Lightning and Munster complete the festival at 4pm.
As ever, the games are broadcast on the excellent livestream - Details on the Cricket Leinster website and Twitter feed.
SCOREBOARD
Northern Knights (5) beat Munster Reds (0) by 39 runs.
Sydney Parade, 7 July.
Northern Knights 165 (20.0 overs, A Dennison 35, P Eakin 25, Yaqoob Ali 2-12, DC Delany 2-33, J Benton 2-34)
Munster Reds 126 (18.2 overs, O Gunning 26, J Mulder 3-18, S Getkate 3-28)
Leinster Lightning (5) beat North West Warriors (0) by 41 runs.
Sydney Parade, 7 July.
Leinster Lightning 182-3 (20.0 overs, J Anderson 76*, G Dockrell 40*, G Delany 28, G Kennedy 2-20)
North West Warriors 141-8 (18.4 overs, D Rankin 37, E Richardson 4-25, G Dockrell 2-22)