The Division Three final between Kirkbymoorside and Seamer 2nds turned out to be a classic final.
Seamer batted first and Connor Myserscough hit a superb 52, and skipper Joe Tiffany added 37 before a late blitz from Dave Allen (20no) took the final score to 163-6 from their 20 overs.
Jamie Harper took 2-18 and Howard Mudd bowled a tight spell of 1-23 from his four overs which included a maiden.
In reply, Martin Charlton and Harper laid siege to the Seamer attack as the pair opened up with 88 in 10 overs.
The introduction of Josh McNeil gave Seamer a chance as he snared both openers Harper for 37 and Charlton for a superb 60.
Wickets began to tumble with McNeill (4-22) and Phil Metcalfe (2-21) bowling fine spells, coupled with Seamer taking some excellent catches, but a fine unbeaten 24 from James Magson saw his side home with just 2 balls to spare.
Martin Charlton was named player of the match for his match-winning 60.
Fylingdales batted first in the Division Two final against Bridlington 2nds but slipped to 20-2.
Chris Shrimpton led the recovery, top scoring with a fine 40 and with contributions from Mark Estill and Guy Shrimpton took Fylingdales past the 100 mark before Carl Parkin (3-21) dismissed all three batsmen.
Ben Ibbotson (3-7) then mopped up the tail with five balls remaining, Fylingdales all out for 133.
Left-arm bowler Estill then struck first over, removing the dangerous Andrew Clay lbw without scoring.
Then an astonishing piece of boundary fielding from Chris Shrimpton accounted for Greg Miller, also for a duck, hitting the stumps from the rope on the longest boundary on the field and Brid were 15-2.
Matty Clay was joined by Steve Lount and the pair steady things before going on the attack. Clay was the aggressor, with left-hander Lount happy to play second fiddle and Clay soon passed 50 and never looked back.
The pair registered a superb century-partnership and despite Fylingdales best efforts and Bridlington were cruising.
Player of the match Clay finished unbeaten on a fabulous 89 with 14 4s and two sixes, while Lount chipped in with 29 not out as they romped home in 16.5 overs to secure an eight-wicket win.
The second T20 Finals Day will take place on Sunday at Flixton, with the Division One clash between Settrington and Wykeham starting at midday and the Premier Division final, Staithes v Seamer following at 3pm.