SHOWDOWN history (or folklore) is built on the themes of all great sporting rivalries around the world: Ignore form, dismiss the standings on the premiership ladder, take the betting markets with a pinch of salt.

If Port Adelaide succeeds as the great underdog in Showdown LVIII on Saturday night at Adelaide Oval, the inevitable question is: Which other upset goes to second place in the grand boilovers in the South Australian AFL derby?

Is it Showdown XXV, the Sunday afternoon clash at Football Park on July 20, 2008, when Port Adelaide - with its season written off by a 4-11 win-loss count before the derby - wrecked the grand wishes of the neighbours on West Lakes Boulevard to finish in the top four? 

Port Adelaide was placed 13th of 16. The rival was in fifth spot but expecting to rise to the top echelon of the AFL ladder with the supposedly inevitable Showdown triumph being forecast by so many.

Port Adelaide had lost five in a row; seven of the previous eight home-and-away matches to have its season (after that grand final appearance 10 months earlier) cast as a "disaster".

Port Adelaide had watched its 11-5 lead in the Showdown ledger put at 12-12 by winning just one of the previous eight derbies (two years earlier in 2006).

The neighbour, by some contrast, had started the season as a pacesetter with an 8-3 win-loss count. It did have an issue - a four-game losing streak - entering the Showdown. But it still commanded favouritism for the derby.

Port Adelaide defied the expectations - and proved the Showdown has its own agenda - with a 12-point win, 13.14 (92) to 11.14 (80). Job done. The underdog had bitten hard, leaving the neighbour outside the top eight after this derby. And the loôk on opposition coach Neil Craig was as cold as the pre-game atmosphere at West Lakes with the thermometer at 9C.

And then there is 2010.

The pre-Showdown script had just as much misery attached to Port Adelaide.

There was a nine-game losing streak, premiership coach Mark Williams had left Alberton two weeks earlier and the premiership table showed Port Adelaide was 14th with a 5-11 win-loss record. In the background there also were political plays as the SANFL and AFL used the Port Adelaide national league licence to further their own agendas. And at home, there was the start of the "One Club" campaign to reunite the Port Adelaide Football Club at AFL and SANFL level. There was a bit going on at Alberton.

Showdown XXIX was the neighbour’s chance to maintain a winning streak - that had reached four - to keep finals on the agenda after a 0-6 start to the home-and-away season (the sixth loss coming in a Showdown). The rival was 7-9 and 10th on the AFL ladder.

The derby marked former captain Matthew Primus’ second game as interim coach. The first had ended in a 36-point loss to the Western Bulldogs in Darwin, a game that was in the balance at half-time.

“We had pushed an opponent for a little longer than in previous games,” recalls Primus, now senior coach of highly-ranked VFL outfit Southport in south-east Queensland. “We were showing we could stay in games longer … we had not done that for a while. It was important for building belief that week.”

Primus recalls the agenda for Showdown XXIX was “set early … set in the build-up to the game against the Western Bulldogs.”

“The situation was as true as many when a club loses a coach and a new coach takes charge,” said Primus. “There is not much you can change. You can deliver a new message. 

“And the timing of the Showdown was very good for a team chasing that next win … Showdowns don’t require much creativity to generate excitement and motivation for a team. 

“At that stage we were still a pretty good stoppage team. We had the basis to play a certain way - the way you need to play to win a Showdown. 

“And then I leaned on the leadership group. Dom Cassisi, Dean Brogan, Chad Cornes … get them wound up and you know how the rest of the group will behave!”

Primus worked a simple - and well-known - theme for a team entering the Showdown in the twilight hour of Sunday, July 25 with the season shot.

“We had nothing to lose,” says Primus. “And a win would hurt the opposition. We had the attitude we would throw everything at them. Everything. 

“And the longer we stayed in this Showdown, the more and more belief we found … and more belief we could win again.

“We did not load up the players with ‘Do this, this, this …’ We started with building their motivation to win. Not that it takes much motivating for a Showdown. Add the theme that you can wreck the opposition’s season and it all builds from there.”

Port Adelaide won the opening term, 2.3 to 1.5; and increased the lead to 10 points at half-time. 

“And we had more belief that we could stay in the game for even longer,” recalled Primus. “The belief kept growing.”

So did the lead. Port Adelaide led by 27 points on the three quarter-time siren. It won by 19 points, 13.10 (88) to 9.15 (69) with captain Dom Cassisi setting the agenda in a classic midfield duel with Scott Thompson. Justin Westhoff and Brett Ebert loaded the scoreboard with seven goals, four and three goals respectively. 

Port Adelaide won five of its last six games.

But the Showdown triumph meant most.

“Pride,” says Primus of the emotion he carried away from Football Park that evening. “And relief.

“It was not the year we had expected. But that Showdown win created excitement amid all the disappointment. We won a hard slog. If we were not to play finals, we were certainly going to enjoy casting the same fate on the opposition.”

Primus notes the Showdown has one true hallmark of a genuine sporting rivalry.

“You have two clubs that hate - or should I say dislike - each other,” says Primus. “Then it was hate. That is why it was an easy sell to our players. 

“I came back to see Robbie Gray’s last game, the second Showdown of 2022. The Port Adelaide players then made it known they hated the team down the road; now you would say they dislike each other.

“And if you are not having the season you wanted, you might as well make sure the neighbours are going to cop a costly loss in a Showdown.

“Both teams, both clubs have an intense rivalry that has built a great Showdown image. History proves it. Look how tight the head-to-head ledger is. It is a great rivalry.”

From afar in Queensland, Primus notes the Showdown story has relevance well beyond the South Australian borders.

“The Showdown has become a moment people across Australia want to watch,” Primus said. “It is the match-up that delivers. It is a good game of football that people want to watch and people understand what the Showdown means.

“It is the game that still torments the loser when they walk down the street the next day … you know there will be a reminder of the result.”