A century from captain Lee Nelson and a hat-trick for Graham Hume were the highlights of Waringstown's dramatic 12-run win against rivals CIYMS.
Nelson hit 103 from 105 balls (11 fours, 3 sixes) as he and Hume (74) shared a century stand for the fifth wicket as Waringstown posted 275 for 8.
James Cameron-Dow (3-65) and Graham Kennedy (2-50) were the most successful bowlers.
The CIYMS chase started strongly with half centuries from the top three - John Matchett, Chris Dougherty, and Nigel Jones - and at 218 for 2, it seemed as if the Belmont side would romp home.
However the game turned on its head as Hume dismissed Graham Kennedy (32), then followed it up to bowl Jason van der Merwe first ball, and trap Jacob Mulder, lbw playing no shot - never a good idea- to claim the hat-trick.
218 for 2 had become 218 for 5 and very much game on. The required rate reached double figures with 23 needed off two overs.
Cameron-Dow was run out, and David Miller bowled by Hume (4-26) to leave an unlikely 17 required from the last.
James Mitchell (2-53) kept cool and conceded just four runs, while accounting for skipper Nigel Jones to seal the 12-run win.
Waringstown have now one hand on the trophy but were forced to wait a while longer as North Down beat CSNI.
Skipper Ally Shields scored 106 as he and Peter Eakin (79) shared a third wicket stand of 114 as the Comber side posted 258 for 4.
Shields, Carl Robinson and Ryan Haire then took two wickets apiece as CSNI were dismissed for 193 - Ross Adair top scoring with 46.
There was another centurion in the third game of the day with Ruhan Pretorius reaching the landmark as Woodvale beat Instonians at Shaws Bridge.
Pretorius hit 11 fours and 2 sixes in a fluent knock, sharing a century stand with Aditya Adey (39) as the Ballygomartin side scored 244 - runs too for James Hall (45), while James Hunter took 4 for 25.
Cade Carmichael top scored with 83 in the Inst chase, but two wickets apiece for Pretorius, Ferhan Saeed, Paul Robinson and Adey clinched a 31-run win.
Woodvale are back in action today (SUN) as they entertain North Down, while Lisburn and Carrickfergus meet at Middle Road.