Post 114 fell behind 2-0 in the top of the second inning but the pitching of southpaw Austin Godwin held Jackson's bats in check the rest of the way.
He threw all nine innings, allowing six hits while striking out seven and walking seven.
Sikeston's offense also came alive to win the game comfortably.
"Austin Godwin was on," Sikeston assistant Matt Johnson said. "A nine inning complete game by a 16-year-old is pretty impressive. They played fundamentally sound all around. That's good to see. They've struggled a little bit this season but they looked pretty good tonight."
Godwin wasn't the only standout for Post 114 as Gavin O'Brien and Zach Downing each went 4-for-4 at the plate.
O'Brien scored two runs and had two stolen bases while playing a solid game at shortstop. Downing also had two RBIs on a double which gave Post 114 the lead for good early in the contest.
"I expected that kind of thing out of Gavin because I know what he's capable of, but I wasn't aware of the Downing kid and he hit the ball well for us," Johnson said. "We've got some good sticks on this team. They played aggressive, we stole some bases, we moved some guys around and had a lot of fun."
After Jackson took a 2-0 lead in the second, Post 114 responded with three runs in the bottom half of the inning. Jared Yates had a fielder's choice-RBI to bring in the first run.
Downing's double into the right field gap brought in two runs.
As Godwin shut down the Jackson offense, Post 114 was able to tack on several insurance runs.
Austin Hatchel had a groundout-RBI in the third to lead 4-2.
Post 114 added two more runs in the bottom of the fourth, including a run-scoring single by John Foster to lead 6-2.
The team scored its final run in the bottom of the seventh when O'Brien slid in safely on a wild pitch.
Jon Winkler was the losing pitcher for Jackson, throwing three inning and allowing five hits and four runs.
Jackson (6-19) pitchers allowed 11 hits to Sikeston hitters and the pitching staff was not helped by a defense that committed three costly errors.
"We've had a difficult time offensively here recently," Jackson coach Tracy Wyatt said. "We left a lot of people on base and a lot of men in scoring position and couldn't bring them home. We've got several players in extended slumps. I wish I could figure it out. We'd be winning a lot more ballgames."
Contrary to Jackson, Sikeston's defense was solid, committing just one error in helping Godwin to the victory.
"He pitched well and he didn't throw the same thing over and over," Johnson said of Godwin. "He changed speeds, he changed locations, he never really gave them a chance to get locked in. They got a couple in the one inning, other than that their bats never got locked in at all and he had them confused all night. I thought he pitched great."
Sikeston (4-16) will host Paducah Legion on Tuesday at 6 p.m.
Jack. 020 000 000 -- 2 6 3
Sik. 031 200 10x -- 7 11 1
WP -- Austin Godwin. LP -- Jon Winkler. 2B -- (S) Gavin O'Brien, Zach Downing. Multiple hitters -- (J) Tyler Koenig 2-4, Chase Steffens 2-4. (S) O'Brien 4-4, Downing 4-4.