Alistair Rickerby was the assassin, as Technical's striker continued his rich vein of form, and left white-shirted defenders on their knees in despair.
The first half was reasonably even, as both teams battled for possession, but Technical always looked bigger and stronger, with a more balanced armoury.
Pace on the wings from Tim McLennan and Ross Howard stretched the Roslyn defence, and when a right wing corner was half cleared, then played back in, it was quicksilver Rickerby who pounced and after seven minutes Technical led 1-0.
Roslyn climbed back into the match, and made several attacking breaks but lacked real firepower.
James Govan, nursing a hamstring injury, was a non-starter on the bench.
Yet, coach Colin Thom was confident that his Roslyn side would compete better in the second half.
Ben O'Farrell and Tennessee Kinghorn combined in tidy passing in midfield and Ben Kiore showed threatening pace.
But from a 47th minute right wing attack, the ball was switched to McLennan in space, and he expertly drilled the ball past keeper Sam Jewell, as the Roslyn defence slumped in unison.
The slump still existed, as from Roslyn's kick-off, negative back-passing allowed Rickerby to pressure defenders, steal the ball, and rejoice as he scored his second goal and leapt with delight.
Roslyn was shell-shocked and Technical might have gone further ahead but wayward finishing and good goalkeeping kept the score at 3-0.
Nature joined the contest as a wild southerly swept along the park and, at last, Roslyn applied some steady pressure on the Technical defence, with a series of freekicks and corners.
But next week's training for coach Thom's side will feature finishing practice as Roslyn struggled to shoot at goal, and Technical keeper Zane Green fielded the few efforts on target.
From a right wing corner, it took a skirmish of frenetic proportions in the Technical goalmouth to eventually allow O'Farrell to force the ball in from close range through a forest of legs and the score was 3-1 as time finally ran out.
An exasperated Thom was far from happy with his side's efforts.
"We had a few 'ho-hum' performances out there, and never produced the intensity we hoped to apply,'' he said.
Technical coach Tony Martin praised Rickerby's valuable contribution of goals and aggressive running.
The maroon defence also received plaudits, and as a coach he appreciated the battle in midfield between his Ben Allan and Roslyn's O'Farrell.
Technical now sits three points behind top team Caversham, and Andrew Brook's Mosgiel is still in contention, three points further back, after a 1-0 win over a strong University side at Memorial Park.
Coach Brook thought his side played well enough to have increased the score, after his son Cody finished off a flowing attacking move that featured Jesse Smith, Callum Flaws, Harley Rodeka and finally striker Brook, in the 15th minute.
But the late southerly blast upset Mosgiel, and with Varsity pushing for the equaliser, adjusted his 3-5-2 formation to a deep defensive 4-5-1 to ride out the storm.
Northern notched its first win of the season, beating Green Island 5-1, with goals from Shaun Richards (2), Dave Henderson (2), and Ryan Hawkins.
In premier women's matches, there were sore backs for goalkeepers as Dunedin Technical beat University B 7-0, and Roslyn-Wakari won 6-1 over Technical Maroons.
Roslyn goals came from, Alex McIntosh (2), Una Madden (2), Holly Johnston and Lilly Robbin.
Today the Chatham Cup, contested since 1923, attracts minnows that have the nerve to enter the national competition, and none more so than Melchester Rovers, which plays Gore Wanderers in the feature game at the Caledonian Ground at 2pm.
