Englishman Denly (76 not out) guided the Sixers to their first victory over the Strikers in four seasons with 10 deliveries remaining.
The asking rate always appeared within reach while Denly was in the middle before effervescent wicketkeeper Josh Philippe (30 not out) turned the chase into a cakewalk in front of 31,810 fans at Adelaide Oval.
Denly absorbed the early departure of fellow opener Justin Avendano, who fell for a duck, and along with Daniel Hughes (24) put the Strikers - and particularly paceman Billy Stanlake who went for 35 runs from three overs - to the sword.
Liam O'Connor ended the threatening partnership with a wrong 'un that disturbed the timber of Hughes before fellow legspinner Rashid Khan struck twice in one over.
The Afghan bowler snared Sixers captain Moises Henriques (16) thanks to a wonderful leg-side stumping from Alex Carey and then Jordan Silk (one) who was caught at slip by Matt Short.
Denly, who came into the match with just 61 BBL runs at 10.16 to his name this summer, had a life on 33 when Cam Valente dropped a high, running return chance.
He made the most of his good fortune in his match-winning 60-ball knock before Philippe broke the back of the Strikers whose 5-150 always looked under-par.
Jake Weatherald (50) and Jono Wells (42no) looked good but the home side needed more contributors.
Carey was run out in the opening over - for the third time in his last four knocks - and skipper Colin Ingram (15) and Short (16) failed to capitalise on promising starts.
Weatherald held the key for the home side with the in-form opener crunching Steve O'Keefe (2-31), this season's leading BBL wicket-taker, for 16 off his first over.
But the left-arm former Test spinner had the last laugh, having Weatherald caught at cover point after switching to the River End.
Wells and Cam Valente (17no) lifted the Strikers' scoring rate late but the Sixers' bowlers, led by O'Keefe, had done enough.
Denly praised the Sixers' clinical display with the ball which laid the platform for the successful chase.
"I thought that (limiting the Strikers to 150) was a fantastic effort," he said.
"Our bowling unit this season has been extraordinary."