Flagmantle is real. Believe it, because you just witnessed a genuine finals performance on a genuine finals stage against a genuine finals team in the middle of July.

The Dockers trailed by 25 points in the second quarter, failed to kick a goal in the first half and danger signs were flashing amid a fear they weren’t handling the occasion.

But then they came out in the second half and played a style of footy that totally crushed the Swans. Fremantle kicked nine goals in the final term to win 15.21 (111) to 10.13 (73)

Alex Pearce was inspirational. Murphy Reid’s reputation grew even more, Josh Treacy was a beast with four goals, Mason Cox heaped pressure on Sean Darcy, Andrew Brayshaw led brilliantly, Judd McVee had a series of huge moments and Jordan Clark just kept running.

Charlie Curnow kicked five goals for the Swans but this was a night that stamped Fremantle as the clear flag favourites.

Finals are won through pressure, composure, experience and skill. Small errors become big errors when the stakes are at their highest. Sydney led the way in all of those departments throughout the first half but Fremantle tore the game to shreds when it really mattered with seven unanswered goals in the final term.

This was an incredible turnaround. The Dockers’ heads were spinning early because they just couldn’t find space.

Pearce was doing a phenomenal job of defending the barrage of inside 50s but when you’re under that sort of pressure, you can’t make any mistakes.

Luke Ryan produced the obvious example of what finals pressure can do to players when he totally forgot that you’re not allowed to rub an opponent on the head. That cost an easy goal.

The Swans led by 19 points at quarter time but Fremantle would have taken heart from being that close given they were playing so poorly.

But not much changed in the second term. Pat Voss won a free kick for holding the ball and Reid took advantage after probably not hearing the whistle. That was a chance lost.

Luke Jackson had three bites at a mark and the ball just hit the ground. That was another opportunity missed. Docker after Docker missed set shots and the groans from the crowd told the story.

And when you’re missing shots, the last thing you want is for the opposition to go forward and seize their chance. Tom Papley loves being the antagonist, he nailed his shot and got straight in Fremantle’s faces.

The desperation for a goal led to Shai Bolton demanding the ball from Mason Cox after the ruckman received a free kick.

Bolton was under pressure and was never going to get a clean shot away. His shot sailed wide and Justin Longmuir slammed the phone into the desk.

They didn’t get another shot for the half and went to the rooms goalless. They’d had chances. They kicked 11 behinds. But zero goals would have been a weight that sat incredibly heavily on everyone despite being only 22 points down.

They returned to the field a different team and showed composure under pressure by not blazing away in the opening minute. They had one kick and 10 handballs before Clark kicked the goal from more than 50m out. Fans had something to cheer for and the monkey was off the back.

The problem was Curnow just kept kicking goals at the other end.

Fremantle took the lessons from the first half though, increased the pressure, hit targets it became a heavyweight bout with both teams trading blows.

Now Sydney lacked composure as Dane Rampe gave Fremantle a shot by slapping Jye Amiss on the head after he gave away a free kick.

Eight goals in 16 minutes became no goals for the next 15. But Reid produced some magic that gave the Dockers space, Amiss took a contested mark, kicked the goal and the margin was three points.

But fighting back is one thing. Hitting the front is another.

When a nervous Rampe wrapped two arms around Amiss ahead of play early in the final term, the Dockers won a free kick and hit the front. But finals always present more challenges and Curnow’s fifth meant Fremantle had to start again.

Pressure was everywhere. Treacy smashed Callum Mills. Pearce ran back with the flight and took and incredible mark. Fremantle then forced a turnover at half-back and got the ball inside 50 where Treacy put them back in front.

And that was all Fremantle needed. Once they got on top, they were unstoppable.

It was goal after goal as confidence grew to extraordinary levels.

The Dockers are now two wins clear on top of the ladder again. Bring on September.

FREMANTLE 0.5, 0.11, 6.16, 15.21 (111)

SYDNEY 3.6, 4.9, 7.12, 10.13 (73)

Goals – FREMANTLE: J Treacy 4 S Bolton 2 M Frederick 2 P Voss 2 J Amiss 2 J Clark J McVee M Cox. SYDNEY: C Curnow 5 T Papley 2 J Lloyd 2 T Hanily.

Best – FREMANTLE: M Reid J Treacy A Brayshaw S Bolton J Clark A Pearce. SYDNEY: C Curnow E Gulden N Blakey T Papley B Grundy C Mills.

Injuries – Nil.

Umpires: H Meyer B Hosking S Meredith N Williamson. Crowd: 55,966 at Optus Stadium.