Zak Butters of the Power smothers the ball during Showdown L.

PORT ADELAIDE is on the verge of its second consecutive top-four finish - and first for an AFL 22-game home-and-away series since 2007.

But at an AFL club living to the mantra of "chasing greatness", rankings are not as satisfying as premierships - as noted by Port Adelaide midfielder-forward Zak Butters.

"We are pretty happy where we are sitting at the moment ... but we are not content," Butters said. 

"We are pretty optimistic as a group," added Butters of the challenges Port Adelaide will face in the top-eight finals next month. "We have done extremely well to bank some wins up through the season and get to this stage where we have ourselves in a pretty good position with two rounds left.

"It is good to have cleared the hurdles we have had through the season to have basically a full-strength team now. So we are looking forward to playing some good footy and to building momentum going into the finals."

With the conclusion of round 21 on Monday night in Perth, Port Adelaide has retained fourth spot - but is equal second with the Western Bulldogs and Geelong that have superior percentages, 138.1 and 129.1 compared to 121.3.

Port Adelaide has achieved a 15-5 win-loss record with two games to play in the home-and-away series - at home to non-contender Carlton and away to premiership fancy, the Western Bulldogs.

At best, a 17-5 record would mark Port Adelaide's best qualifying season since the premiership-winning year of 2004 (also 17-5).

04:14

Butters' review of Showdown L - won by Port Adelaide by four points at Adelaide Oval on Saturday night - continues the theme that the South Australian derbies defy form, premiership rankings and betting charts.

"It was Showdown footy," said Butters. "It was just what Showdowns are expected to be - real close, contested footy, pretty manic. There was a lot of pressure and that made it a hard-fought, scrappy and quick game. And a weird one ...

"Adelaide, to their credit, played a good game. So at half-time (after scoring just one goal) we had to lift. 

"Sometimes you just have to win dirty."

Port Adelaide advanced its Showdown win-loss count to 26-24 after again being tested by a rival determined to work against the strengths of Ken Hinkley's playbook.

"We were forced into a lot of long kicks down the line and getting a lot of players to the ball (while Adelaide wanted) to outnumber us," Butters said. "There were a lot of contests in the game, a lot of scrappy, dirty ball. 

"We like to win it and go from there. When it is scrappy and dirty that is harder to do. So credit to them - and we probably did not match it quick enough and that is why they had a lead on us in the first half."

07:27

Hinkley's half-time address focussed on the true barometer of Port Adelaide this season, the need for strength at the contests.

"We probably did not train the best on Thursday and that is something Ken brought up at half-time," Butters said. "He was pretty fired up because our contest work wasn't great and we were getting out-worked at stages. That is something that is non-negotiable at our footy club. Ken was not happy with that and he let us know what he was thinking. 

"The boys responded well. You know when Kenny gets angry he means business. And you know you have some work to do."

Port Adelaide's hold on a top-four ranking while waiting for reinforcements from the injury list adds merit to the squad mentality taken up at Alberton this year. The next phase of this script is to find form, both in individuals coming back from long stints on the sidelines and with the team game.

"I feel going better going into each game," said Butters who has dealt with a knee injury and two ankle injuries this season. "My first game back was on adrenalin. The next few weeks I am looking to really hit my straps and be firing. Now is the time to do it.

"Hopefully, we will get Steven Motlop back (from an ankle injury) this week. He is an important player to our team; he brings a lot of speed in that critical high half-forward role."