Young star Jaylin Galloway has fired off the bench as Sydney stifled Tasmania's high-powered attack to lay the platform for a gutsy 90-82 road win.
Rated the NBL's worst defence by some margin entering round 11, the Kings had coughed up triple-figure scores in three of their previous four outings.
And it didn't look good when they conceded 24 points in the opening quarter in Hobart on Sunday.
But Sydney restricted the JackJumpers to just nine points in the second term - one more than the competition-low for a quarter so far this season.
It gave the Kings a 39-33 lead at the main break and they went on with the job, resisting a final-quarter fightback from the hosts to keep their noses in front.
The visitors' lead was cut to one point and then briefly ballooned to 11 before a huge Galloway dunk with two minutes left looked to have shut the gate.
But Tasmania kept fighting to the final buzzer despite being forced into a club-worst 19 turnovers.
Sydney coach Mahmoud Abdelfattah revealed an unorthodox preparation was key to his team's improved defensive showing.
"We gave them extra days off," Abdelfattah told reporters post-game.
"We went to Bondi one day and Bronte beach the other day just to be able to understand that life is bigger than basketball and clear your mind.
"That was it. Guys came ready to compete and I thought they put forward their best effort and showed what they can do."
NBA prospect Galloway starred for Sydney, scoring a career-high 24 points on 8-of-11 shooting.
The 20-year-old produced a series of cool finishes and scored 10 points in the third quarter alone to give the Kings a strong foothold in the contest.
"He did a phenomenal job on both ends on the floor," Abdelfattah said.
"He did a hell of a job attacking the basket, not settling, taking the right shots ... but (also) the pressure that he put on the rim, he had a couple of big steals and forced a number of big turnovers."
Former league MVP Jaylen Adams (13 points, 10 assists) produced a double-double and was one of five Sydney scorers in double figures.
The Kings (9-6) moved up to second spot on the ladder behind Melbourne United (13-3) as they chase a third consecutive championship.
It was Tasmania's (9-7) second loss of round 11, sending them sliding to fourth.
Jack McVeigh (23 points) and Jordon Crawford (22) fought hard in a losing cause for the JackJumpers, who coach Scott Roth conceded were simply outplayed.
"All credit to (Sydney). They were in the passing lanes and knocking some passes and we were a little sloppy with the ball and a little loose with it," Roth said.
"They made things difficult for us and I think we were just a little sloppy."