Bolton showcased his elite talent in wet and wild conditions, kicking three crucial goals in the Dockers' precious 11.9 (75) to 9.10 (64) win at People First Stadium on Saturday.
A third straight victory lifted Fremantle (7-5) into the top eight, while the Suns (8-3) suffered just their third loss of the season and first on home turf.
Highlighted as the Dockers' "barometer" by his former Richmond boss Damien Hardwick in the build-up to the game, Bolton lit up the front half of the ground with 20 disposals.
His late tackle on Nick Holman was every bit as important, directly leading to Jye Amiss's match-sealing goal in the final 30 seconds.
Fremantle kicked five of the first seven goals in a see-sawing contest that swung on stoppage control, and surged to a game-high 20-point lead early in the final term.
But the Suns rallied and registered the next five scoring shots to close within five points, before Bolton sparked the match-winning moment.
"He's happy to play whatever role we ask of him, and he played a little bit more forward today and had an influence in the front half," Longmuir said.
"He's been super. He's done everything we've asked him to do."
Luke Jackson (27 disposals) was influential again in a hybrid ruck-midfield role for Fremantle, and Patrick Voss stood tall in attack, tallying a career-best three goals and eight tackles.
Caleb Serong (27 disposals, six clearances), Jordan Clark (30, five) and stand-in captain Andrew Brayshaw (30, five) were also key contributors.
Brayshaw was crunched in a huge hit from Daniel Rioli in the desperate final stages and umpire Brett Rosebury immediately called for a doctor to assess the tough Dockers' midfielder, who got up and took his kick.
"I had a few boys come up to me and say it was a perfect time to get hit. They were screwed, they needed a spell," Brayshaw told Fox Footy.
"But we played with our hearts on our sleeves tonight and it was a really tough contest.
"These guys are amazing, so to get a win's huge."
Gold Coast captain Noah Anderson was immense with game-high tallies of 39 disposals and 12 clearances.
Fellow midfielders Matt Rowell (27 disposals, eight clearances) and Touk Miller (24, nine) were also busy, and Jed Walter kicked two goals.
Suns academy graduate Leo Lombard provided a highlight and sparked wild celebrations among his teammates with a goal on debut.
Sam Flanders kicked three majors, including an audacious effort off the ground with the outside of his right boot.
It was one of his two goals in the final term, but Gold Coast couldn't ride their momentum all the way.
Mac Andrew was swung forward late and missed a set shot around his body from the boundary that could have tied the scores, before the Suns were ultimately thwarted by Bolton.
"We did have a play on that far side and then Shai Bolton made a hell of a tackle," Suns coach Hardwick said.
"It was a great bit of play and there's a reason he's one of the best players in the comp - it's for things like that.
"If we get that ball out we might've gone down and given ourselves a chance.
"But moments are pretty special, and that was a pretty good moment by Shai."
Rowell was reported on the spot for high contact on Neil Erasmus with his left hand, but is unlikely to face sanction after the incident is properly assessed.
Nat Fyfe made his long-awaited return from a string of injuries as Fremantle's substitute and played an important role with seven disposals and some important touches in the final quarter.
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