Welcoming the Mariners to McDonald Jones Stadium on Saturday, the Jets were ruthless against their at-times hapless foes.
The home side took an early lead through Aleksandar Susnjar, then piled on the goals after Storm Roux's 39th-minute red card.
Saturday's six-goal margin was the equal heaviest in F3 Derby history - matching the Jets' 8-2 win in 2018 - and left the Mariners nine points outside the top six with two games remaining, ending their run of fairytale back-to-back championships and forcing them to watch the playoffs from home for the first time since 2019-20.
"First and foremost, I want to apologise to our supporters," Jackson told Paramount+.
"I've not had to do that many times in my career, but I feel it's necessary tonight.
"In a local derby to produce that on the pitch in front of a big following is not acceptable."
Five points outside the top six with just three games to play and already having announced that coach Rob Stanton will not be returning, the Jets are also unlikely to play finals but secured derby bragging rights for the first time since December 2022.
"We'll keep an eye on (the ladder), but we just need to keep focusing on what we can control, and that is our performances for these remaining games of the season," Jets attacker Eli Adams told Paramount+.
Clayton Taylor ran the show for the hosts, the 21-year-old assisting Susnjar and Daniel Wilmering's goals, and inducing Mariners skipper Trent Sainsbury to turn the ball into his own net on the stroke of halftime.
Taylor then made it 4-0 with a long-range laser in the 50th minute.
Coached in the Sydney FC academy by Stanton, Taylor followed the coach to the Hunter after his appointment and expressed regret over his departure.
"It's very disappointing to lose Robbie," Taylor told Paramount+.
"I think we're just starting to find our footing and performing really well, especially over the last few months."
Kota Mizunuma set up Adams for the fifth in the 73rd minute, and the youngster grabbed a second in the 92nd.
Reflective of the Mariners' evening, Roux's red came just eight minutes after he came on for the injured Mikael Doka, lashing out with an elbow following a tussle with Callum Timmins.
