The teenage all-rounder impressed with both bat and ball as last season’s grand finalist accounted for Tongala by 81 runs at Cohuna Recreation Reserve.
Batting first, Nondies-Cohuna lost openers Broden Wishart and Karim Marcelle early to be on the back foot at 2-12.
But teenager Sussex illustrated a composure beyond his tender years to rebuild the innings.
Batting at three, the Welshman hit 10 boundaries and a towering six during his brilliant hand of 70, coming from just 90 deliveries.
He shared a 64-run stand with Rhys Bradley (24) and then put on 56 alongside Will O’Shea before he fell at 6-123.
The early platform would have counted for little unless the Nondies-Cohuna lower order displayed some resistance.
The seniority of vice-captain Zeb Ellwood and skipper Kyeran Ellery did just that.
Ellwood made a run-a-ball 25 and Ellery a breezy 20, highlighted by two sixes, as the hosts reached 175 despite being bowled out in 41 overs.
Rory Knight was the standout of the Tongala bowlers, collecting 4-27 from his six overs.
Skipper Alex Williams (2-20) also bowled well and claimed the key wicket of Sussex.
Tongala’s hopes of chasing down the target and sealing a first win since returning to the top-flight endured an early blow when Knight was bowled by Xavier Wishart for a fourth-ball duck.
Sam O’Shea supported his fellow opening bowling partner, dispatching Keagan Miller and Stephen Townsend in quick succession.
Blues captain Williams stood tall, hitting three boundaries, but the introduction of Leigh Johnson to the attack saw his knock come to an end on 22.
Ryan Smith (16), Matt Ohlsen (14) and Luke Smith (13) all reached double figures for Tongala, although it never really looked a hope of claiming the points, bowled out for 94.
Sussex followed up his batting heroics to claim 2-9 from four overs.
O’Shea (3-11) bowled superbly for Nondies-Cohuna and Wishart (2-26) also impressed.
THE GAME
Nondies-Cohuna 175 (Archie Sussex 70, Zeb Ellwood 25, Rhys Bradley 24, Kyeran Ellery 20, Rory Knight 4-27, Alex Williams 2-20) defeated Tongala 94 (Alex Williams 22, Sam O’Shea 3-11, Archie Sussex 2-9, Xavier Wishart 2-26).