Cachopa struck five boundaries and four sixes while occupying the crease for 40 minutes after skipper Kieran Noema-Barnett won the toss and chose to pad up before the floodlights kicked in.
The Alan Hunt-coached Stags amassed a respectable 6-140 from their allotted 20 overs with opener Jamie How contributing 21 runs but offering a soft cough and bowled dismissal to Lancashire import Steven Croft.
CD assistant coach Lance Hamilton, who spoke just after the Stags took the field, said Cachopa's hard work in winter was paying dividends in not only the four-day campaign - CD are on the top of the shield table - but also in the shorter format now.
"Chops is full of confidence and scoring runs," the former CD and Black Caps seamer said, adding the team plan was always to bring Cachopa at No 6 to ensure he played his educated shots to carry his bat through the innings.
"He did that superbly tonight," he said of Cachopa who carved up a patient fifth first-class career century against the Auckland Aces in Napier early this month on the heels of as many shield matches.
"Chops hits the ball in good areas and all in front of the wicket," he said of the South African born in Bloemfontein.
Cachopa smashed ND bowler Graeme Aldridge for 19 runs off one over and they were all square off the block.
"It's a pretty difficult wicket to bat on because it's gripping and holding quite a bit," Hamilton said.
At the halfway mark, the CD coaching stable had impressed on their bowlers not to offer to full deliveries.
"We're looking at bowling back a length but as I'm saying that to you Milney has just bowled a full one and he's gone," Hamilton said, adding half volleys were inviting to be smacked into orbit.
Earlier, the Stags' English import Peter Trego didn't have a dream start with the bat, falling prey to ND skipper Scott Styris for five runs after mistiming a disguised delivery down the throat of Corey Anderson at cover.
Trego did deliver with the ball, 2-30 off four overs.
No doubt the Somerset county cricketer will try to emulate ND import Steven Croft who took 2-12 from two overs and was unbeaten on 59 runs with the bat in a lucrative partnership with Lancashire import and former England wicketkeeper James Foster who was not out 26.
Playing at No 4, Croft scored off 48 balls, including six fours and a six.
With six runs needed from eight balls, any sniff of victory that CD had succumbed to gravity when Ben Wheeler dropped a catch in breaking the partnership at deep backward of point in what can perhaps best be put down to not picking the ball in the night light.
Wheeler took 2-23 from 3.1 overs but in the mould of most of the Stags bowlers, he did the job but there wasn't enough venom to make the hosts sweat enough to cough up wickets at crucial intervals in CD's opening HRV Cup T20 clash.
Scoreboard
From last night's HRV Cup Twenty/20 match between Devon Hotel Central Districts Stags and the Northern Districts Knights at Seddon Park, Hamilton:
Toss: CD Stags, batted.
CD Stags
P Trego c C Anderson b S Styris 5
J How c&b S Croft 21
D Robinson c C Anderson b G Aldridge 3
M Sinclair st J Foster b Croft 13
K Noema-Barnett c&b A Devcich 15
Carl Cachopa not out 64
W Young run out (J Marshall/Foster) 5
M Kain not out 12
Extras (0b, 9Lb, 2w, 0nb): 11
Total (6 wkts, 20 overs): 149
Fall: 1-9 (Trego, 1.6), 2-17 (Robinson, 5.2), 3-48 (How, 9.1), 4-49 (Sinclair, 9.6), 5-79 (Noema-Barnett, 14.3), 6-104 (Young, 16.4).
Bowling A Devcich 4-0-15-1 (1w), S Styris 4-0-20-1, B Arnel 3-0-23-0 (1w), G Aldridge 3-0-40-1, B Scott 4-0-30-0, S Croft 2-0-12-2.
ND Knights
Chasing target: 150 runs.
B Wilson c M Sinclair b P Trego 9
A Devcich b Trego 10
B Watling c Trego b B Wheeler 1
S Croft not out 59
S Styris lbw Wheeler 46
J Foster not out 26
Extras (0b, 0Lb, 2w , 0nb): 2
Total (4 wkts, 19.1 overs): 153
Fall: 1-9 (Wilson, 1.1), 2-16 (Watling, 2.4), 3-20 (Devcich, 3.4), 4-100 (Styris, 14.4).
Bowling: B Wheeler 3.1-0-23-2 (1w), P Trego 4-0-30-2, A Milne 4-0-35-0, T Nethula 3-0-23-0 (1w), M Kain 4-0-26-0, K Noema-Barnett 1-0-16-0.
Result: ND won by 6 wkts.12th men: D Mitchell (ND), A Patel (CD).
Umpires: WR Knights and PJ Agent.
Scorers: DM Plummer and PG Rice.
