Port Adelaide started its competitive football campaign 150 years ago today with a 1-1 draw. Tonight, it needs to celebrate the moment with a win - against Australia's oldest football club, Melbourne.

By unfortunate accident with the COVID pandemic rather than strategic design, Port Adelaide gains a stand-alone spotlight moment for its 150th anniversary match - including national free-to-air television coverage.

And the game is played in Brisbane.

None of this was imaginable when the Scottish-born John Wald led Port Adelaide onto the north parklands near Adelaide Oval on Saturday, July 30, 1870. He became the Port Adelaide Football Club's first (and only) goalscorer in the 1-1 draw with the equally new (but short-lived) Young Australian team that was based in the Adelaide city district.

Standing shoulder-to-shoulder with the Melbourne Football Club, formed in 1858, would have been a reasonable ambition for Port Adelaide's foundation clubmen. It still was the dream in the 1950s when Port Adelaide captain-coach Fos Williams and Melbourne coach Norm Smith repeatedly put their SANFL and VFL superpowers against each other. Those end-of-season "champions" matches under floodlights at Norwood Oval allowed ambitious men such as Williams and Bob McLean to envision a grander future with a national competition for Australia's homegrown national game.

This time, under the lights of the Gabba cricket ground, Port Adelaide it is not taking the field for fun as it was in the pre-league games of 1870 or for bragging rights as in the exhibition matches of the 1950s. This round 9 match is for four AFL premiership points and a grip on a top-eight berth to October's top-eight finals.

Tonight, the oldest-surviving foundation clubs of South Australian and Victorian football meet for the 35th time since 1997 in the national Australian Football League. Port Adelaide leads the head-to-head count 21-13 and has won nine of the past 11 clashes between the pioneer clubs.

Despite a 6-2 win-loss count that keeps Port Adelaide at the top of the AFL ladder - and exceeding external pre-season expectations that Ken Hinkley had a team that would be grappling for a finish between sixth and eighth positions - there is still a question mark on where Tom Jonas' team fits in this complicated AFL season. Still, that could be said of 11 of the 18 AFL clubs today.

Will there be clarity or confusion at the end of this 33-game, 20-day sprint of games on quick rotation to rush the season through rounds 9-12?

"We are top of the ladder - a position we have earned," says Hinkley, "and we'll be doing our best to protect that position."

ROUND 9

Melbourne v Port Adelaide

GLASS half full or half empty?

Well, at least - with such a quick turnaround to this round 9 match at the Gabba - neither Port Adelaide nor Melbourne need to get into a long debate on how to measure their weekend losses to St Kilda and Brisbane respectively. Both need a quick response, however. Only one can achieve this aim (unless July 30, 1870 is relived to the finest detail with the first draw between Port Adelaide and Melbourne).

Glass half full for Port Adelaide is the thought the players have boldly responded when challenged earlier this season - beating Greater Western Sydney, while marked as the underdog immediately after the second-quarter collapse to Brisbane at the Gabba in round 5.

Glass half full for Melbourne by the promise noted from its last-quarter fightback against Brisbane. This suggests Simon Goodwin has a team that will work at its challenges (so many of them self-indicted) rather than crumble.

Glass half empty for Port Adelaide with its attack losing young forward Todd Marshall for six weeks with a broken thumb. But opportunity opens up for first-year forward Mitch Georgiades - and it stretches the question mark on how Port Adelaide mixes and matches its forward set-up around Charlie Dixon and pinch hits in ruck. The question deepens with the form lapse noted with veteran pinch-hitting ruckman-utility Justin Westhoff.

Senior coach Ken Hinkley has kept Westhoff for the ruck dilemma and virtually ruled out Dixon rediscovering the centre circle saying: "Charlie is a big boy, but it's unlikely we'll put him in ruck. He is a big presence in our forward half and we'd like to keep him there."

Glass half full again for Port Adelaide - while novice ruckman Peter Ladhams covers for the injured Scott Lycett - with the statistics noting it does not need to beat Melbourne's All-Australian ruckman Max Gawn to win the match. Melbourne convincingly won the centre ruck battles 15-2 against Brisbane, but failed to convert this to a game-defining advantage by clearing the ball from the centre bounces (won 11-6 by Brisbane). For those with a tape measure, Brisbane gained 443 metres from the centre bounces; Melbourne, 201 metres.

Of course, these numbers only matter if the midfield is moving the ball with impetus. "We tend to overuse the ball early in the game," notes Port Adelaide assistant coach Nathan Bassett who labelled the team's ball movement as "bland - safe and basic".

The focus is again on the Port Adelaide midfield - and not just because of the questions posed by the St Kilda loss. Melbourne does present a test of pride for the Port Adelaide midfielders who are charged with resisting Gawn and his battery, in particular Christian Petracca, the handball machine of Clayton Oliver and the courageous Jack Viney, who by the tape measure advanced his team 461 metres at Metricon Stadium at the weekend.

There is plenty falling on the shoulders of vice-captain Ollie Wines, former captain Travis Boak, the out-of-sorts Robbie Gray, young gun Connor Rozee and young bull Sam Powell-Pepper in this match - and that deep rotation of wingmen that involved Xavier Duursma, Karl Amon, Zak Butters and Kane Farrell at the weekend.

Behind the midfield, there is the match-up of two former Gold Coast team-mates - Dixon against Melbourne key defender Steven May (who will have the intercept support of Jake Lever). The backchat could be as fascinating as the one-on-two contests.

Port Adelaide and Melbourne will play on "neutral" territory for the seventh time with the previous six being in the Northern Territory. Port Adelaide has a 4-2 advantage when there is no true home-field advantage.

DANCE CARDS

AT half-time, Port Adelaide will be at the halfway mark of this extraordinary 17-round "home-and-away" season. At best, Port Adelaide will be on the way to a 7-2 win-loss count.

How has Port Adelaide fared at the halfway point of previous AFL seasons - that have involved 22 rounds in the qualifying stages - since joining the national league in 1997?

BEST record after round 11: 10-1 in 2014 with the season ending in the preliminary finals.

WORST record: 1-1-9 in 2000 that ended with an encouraging pointer with six wins in the last 10 matches.

BETTER than 50-50 (at least six wins): 13 times with grand final finishes in 2004 (7-4) and 2007 (6-5); and finals in six other seasons (2001, 2002, 2003, 2013, 2014 and 2017). No finals, however, in the inaugural season of 1997 (6-5), 2009 (6-5), 2016 (6-5), 2018 (7-4) and last year (6-5).

WORSE than 50-50 (five wins or less): 10 times with top-eight finals achieved twice, in 1999 for the first time (after a 5-6 start) and 2005 with the premiership defence opening on a 4-1-6 record.

Port Adelaide this year will be achieving its 14th "better than 50-50" record at the halfway mark of the minor round. More often than not (8-5), Port Adelaide finishes the qualifying rounds with a finals berth.

SELECTION TABLE

Port Adelaide

TWO forced changes - in defence, Jarrod Lienert returns to cover the loss of Riley Bonner; Tom Rockliff resumes to deepen the midfield options while the attack loses Todd Marshall with a broken thumb.

Bonner remains sore from the heavy blow he took to his left side during the third term of Saturday night's match at Adelaide Oval.

On the sidelines remain, key defender Trent McKenzie (back spasms) and AFL premiership-winning ruckman Scott Lycett, who is slated to return from a knee injury in the Monday nightclash at Adelaide Oval against the Western Bulldogs.

The key notes from these two changes are: Justin Westhoff remains in the match 22 to answer needs in defence, attack and in ruck. He is the "everywhere" man again.

Lienert plays his second AFL game of the season - and first since he was the late call-up against Gold Coast in round 1 in March. It will be his 15th AFL game in three years.

Rockliff resumes after missing three AFL matches  - and will play his 13th career game against Melbourne. He averages 27 disposals against the Demons.

In: Lienert, Rockliff

Out: Bonner (bruised hip), Marshall (broken thumb)

Melbourne 

Melbourne has loaded up the tall timber by recalling key forward Tom McDonald to join Luke Jackson and Sam Weidemann in seeking an advantage on the recast Port Adelaide defence.

McDonald kicked four goals in the Melbourne scratch match at the weekend.

Simon Goodwin also recalled former South Adelaide midfielder Tom Sparrow while casting off defender Neville Jetta.

Fremantle recruit Harley Bennell is to be rested. After a three-game run, Goodwin - with the advice of former Port Adelaide fitness coach Darren Burgess - decided it best not to push Bennell on a short turnaround between matches.

In: T. McDonald, Sparrow

Out: Bennell (managed), Jetta 

BIRD SEED

(the little stuff that counts most)

Where: Gabba, Brisbane

When: Thursday, July 30

Time: 7.20pm (SA time)

Last time: Port Adelaide 12.15 (87) d Melbourne 9.7 (61) at the MCG, round 1, March 23 last year 

Overall: Port Adelaide 21, Melbourne 13

Past five games (most recent first): W W L L W

Scoring average: Port Adelaide 95, Melbourne 83

Tightest margin - Port Adelaide by three points (72-69) at Adelaide Oval, round 18, July 20, 2014; Melbourne by one point (111-110) at Marrrara Oval, Darwin, round 9, May 22, 2010.

Biggest margin - Port Adelaide by 89 points (163-74) at Football Park, round 17, July 29, 2007; Melbourne by 53 points (124-71) at the MCG, round 4, April 17, 2004.

By venues - Adelaide Oval (3-1); Football Park (11-2); MCG (3-8); Marrara Oval, Darwin (1-2); Traeger Park, Alice Springs (3-0).

By States and territories - SA: 14-3; Victoria: 3-8; Northern Territory 4-2.

FORM LINES

Port Adelaide

L W W L W W W W

JULY has tested Port Adelaide. It began with the loss to Brisbane that prompted a rethink about the midfield rotations. It demanded a response against 2019 AFL grand finalist Greater Western Sydney - and the Port Adelaide players delivered with a commanding last-quarter surge against one of the AFL's most-talented lists. That victory was backed up by a resilient performance, as coach Ken Hinkley put it, against Carlton with victory sealed on Robbie Gray's accurate kick from the boundary at the Gabba after the siren.

But on the return to Adelaide Oval on Saturday night, after a six-week run in Queensland, the verve disappeared with a slack performance in the midfield against a confident St Kilda unit. Again, a response is demanded.

Melbourne

L W W L L W L

PARODY accounts on social media do have a way of getting very close to the bone. Such as the one from the "AFL integrity unit" on Twitter during Melbourne's four-point loss to Brisbane at Metricon Stadium on Sunday: "Melbourne have almost finished their exhaustive encyclopedia of ways to lose a football game." Certainly the mistakes by the Melbourne players in the open face of the goalfront - either to score goals or defend against any score - were costly.

Melbourne's form line is erratic - lost to West Coast in Perth by 27 points immediately after AFL chief executive Gillon McLachlan announced the season was going into lockdown; followed by a one-point win against Carlton on the restart, three-point loss to Geelong, 27-point defeat to Richmond (when the pressure built on coach Simon Goodwin), 17-point win against Gold Coast, 43-point workover of Hawthorn and the four-point loss to Brisbane at the weekend.

NAUGHTY DEMONS

Melbourne presented to Port Adelaide in the summer of 1999-2000 one modest player who became critical part of the breakthrough 2004 AFL premiership triumph - Matthew Bishop.

And from that premiership 22, one Port Adelaide hero is returning the favour to Melbourne as its football chief seeking to end the 56-year drought for the Demons - Josh Mahoney.

Bishop had played 18 games for Melbourne in 1998-1999 before joining Port Adelaide to become a regular in defence with 132 AFL games until his retirement at the end of 2006 when he became a valuable part of the football staff amid challenging times of change at Alberton.

Mahoney finished his AFL career (that also included stints at Collingwood and the Western Bulldogs) with his 67 national league game at Port Adelaide in 2007. He immediately moved to Melbourne to be an assistant coach from 2008-2011 before taking charge of the football department in September 2011.

The most notable export from Port Adelaide to Melbourne is defender Danny Hughes. He was pick No.13 in the first VFL draft that allowed the 12 Victorian-based clubs to take turns in claiming talent from outside of Victorian borders.

While the draft was legally challenged and struck down, Hughes did move to Melbourne to play 124 VFL-AFL matches from 1981-1990. He was Melbourne's best-and-fairest champion in 1985.

Hughes returned to Port Adelaide in 1991 to play three SANFL seasons before retiring with a 130-game tally at Alberton and his name on a locker.

Port Adelaide forwards coach Nathan Bassett started his AFL career on Melbourne's rookie list in 1997. Injury denied him any senior game before being traded to Adelaide at the end of the season.

QUOTE OF THE PRE-GAME

"We were pretty bland with the ball; we played safe and basic ... it was probably one of the worst performances in the mid-arc area in the last seven years."

Port Adelaide forwards coach Nathan Bassett setting the agenda for the midfield to respond in a serious test against the Melbourne engine room.

TIP

Port Adelaide by three points.