In his eighth season in the open class and claiming his 12th win in 56 finals, Roberts, a former Golden Shears junior and senior champion, ultimately claimed victory by a margin of 3.6pts - as the combined time and quality points result matched the order in which the shearers had come off the board.
It also catapulted him onto the Shearing Sports New Zealand open shearing rankings top-six leaderboard, after four events.
Roberts is now in third place behind fellow Southland shearers Nathan Stratford, of Invercargill, and Troy Pyper, now based in North Canterbury, neither of whom competed at Ashburton.
De Lacy was a comfortable 2.58pts clear of third-placed Duncan Leslie, of Owaka, who was in his second final in the open grade.
Ashburton shearer Taare Edwards extended his lead in the senior rankings with a second win and fourth top-two placing in the grade's four events this season.
North Canterbury-based Reuben King, from Central Hawke's Bay, scored his second win in two intermediate outings, after 11 wins in the junior grade last season, and Lincoln College student Josh Devane, from Taihape, scored the third junior win of his career and also now holds No 1 ranking in his grade.
Veteran Fairlie blade shearer Tony Dobbs, who last year claimed his 100th blade shearing win, scored his second win in two outings in this season's events with the blades.
Hopes for over 50 shearers across the five grades fell short with just 35 on the day.
The numbers disappointed competition convener Don Ford, who believed confirmation of more Covid cases in Christchurch at the end of last week stopped some wary competitors from making the trip.
"It was a bit weird not having any spectators," he said.
"It was a brilliant day, got very warm later on, those who were there had a good day and the open final was just incredible, a very exciting final."
It enabled a local open and senior shearers event which became an all-Proshear showdown, won by "the boss", Rakaia contractor and veteran top open shearer Grant Smith.
The challenge will be for considerably greater numbers next Saturday, with the clash of the Pleasant Point Gymkhana Shear, about 70km south of Ashburton, and the Marlborough A and P Show shears in Blenheim, both also in the Covid Level 2 conditions.
The "Get to the Point" street day, which the Gymkhana Shears are part of, with a four-stand board trucked into the main street, has been cancelled.
However, the Shears will still be held but relocated to the Pleasant Point Domain.
Results from the Ashburton A and P Show Shears on Saturday, October 30, 2021:
Open final (20 sheep): Brett Roberts (Mataura) 18min 30.885sec, 62.69pts, 1; Hugh De Lacy (Parnassus 19min 5.79sec, 66.29pts, 2; Duncan Leslie (Owaka) 20min 5.46sec, 68.87pts, 3; Lyall Windleburn (Rangiora) 20min 10.46sec, 70.82pts, 4; Willie McSkimming (Oamaru) 20min 57.05sec, 75.7pts, 5.
Senior final (9 sheep): Taare Edwards (Ashburton) 12min 12.24sec, 45.17pts, 1; Mitchell Menzies (Ranfurly) 12min 0.67sec, 45.59pts, 2; Adam Hodges (Geraldine) 13min 30.67sec, 50.53pts, 3; Emily Te Kapa (Scotland) 12min 4.94sec, 53.14pts, 4.
Intermediate final (5 sheep): Reuben King (Rangiora) 12min 52.36sec, 48.02pts, 1; Chase Rattray (Ashburton) 12min 40.42sec, 51.62pts, 2; Blake Crooks (Timaru) 13min 3.48sec, 55.57pts, 3; Savvy Taitoko (Pio Pio) 16min 32.37sec, 67.42pts, 4; Mitch Klever (Cave) 10min 47.42sec, 75.77pts, 5.
Junior final (4 sheep): Josh Devane (Taihape) 9min 21.68sec, 37.33pts, 1; Lachie Crafar (Rangiwahia) 11min 41.85sec, 45.84pts, 2; Lydia Thomson (Rangiora) 13min 24.64sec, 50.58pts, 3; Robyn Krause (Germany) 11min 50.75sec, 51.79pts, 4; Sarn McCone (Geraldine) 13min 57.47sec, 60.37pts, 5.
Open Blades (4 sheep): Tony Dobbs (Fairlie) 12min 4.68sec, 43.73pts, 1; Tim Hogg (Timaru) 13min 46.91sec, 50.1pts, 2; Noel Handley (Rangiora) 12min 3.65sec, 53.43pts, 3; Mike McConnell (Waikari) 14min 8.2sec, 56.66pts, 4; Phil Oldfield (Geraldine) 5.
Open/Senior Local (5 sheep): Grant Smith (Rakaia) 6min 17.59sec, 22.28pts, 1; Toko Hapuku (Methven) 5min 11.92sec, 23.64pts, 2; Taare Edwards (Ashburton) 6min 42.73sec, 26.34pts, 3; Duncan Leslie (Owaka) 5min 29.12sec, 27.26pts, 4; Adam Hodges (Geraldine) 7min 45.83sec, 28.09pts, 5.
