FREMANTLE coach Ross Lyon suspected his side's round 23 clash against Port Adelaide would prove pivotal immediately after the Dockers' narrow loss to Geelong in round 20. 

"I would imagine we're fighting for a top-four spot, let alone top-two," Lyon said in the wake of David Mundy's post-siren miss that denied the club a vital win.

His prediction of three weeks ago has come to pass, with Fremantle needing to beat Port Adelaide on Saturday to clinch the top-four spot it has held since round 14 finished.

The game shapes as a classic precursor to the finals. 

Fremantle is in good form. It is the No.1 team in contested possession differential and fourth for total contested possessions. 

It has scored more than 100 points in the past two weeks and averaged 27 points a quarter since three-quarter time against Geelong in round 20. 

The Dockers have scored 70 points fewer this season than in 2013 but they have looked more dangerous lately than at any point last season, and their percentage is better.  

Michael Walters has returned to add an X-factor to the team, joining Hayden Ballantyne and Hayden Crozier to give Fremantle three small forwards capable of kicking goals and putting pressure on the opposition. 

It's no surprise that in the past month Fremantle has spent 3.48 minutes per game more than its opposition in the forward half to be ranked fourth on that measure. Freo was ranked 11th on that statistic after the first 18 games. 

The Dockers' tackling differential has gone from 15th in the first 17 rounds to ninth in the past four games. 

Tendai Mzungu's return and Matt de Boer's reprieve (as a late inclusion for the sore Matthew Pavlich in round 22) have helped in the past fortnight, too. 

Ballantyne's good form is essential to Freo's prospects. The Dockers have won 29 of the 30 games in which the cheeky forward has kicked three goals. 

That one loss came in Ballantyne's second game, way back in round 14, 2009 when he kicked three goals in a defeat against Carlton. 

When Ballantyne is kept goalless – as in last year's Grand Final – the Dockers have won just 52 per cent of the time.  
WHY BALLANTYNE IS SO IMPORTANT TO FREMANTLE
 WITHWITHOUT
MatchesWinsLossesWin %WinsLossesWin %
104673664102429

3+ GOALS FROM BALLA0 GOALS
WinsLossesWin %WinsLossesWin %
29197131252

Fremantle is scoring from stoppages (31.8 per game from rounds 1-18 to 36.2 per game in the past four games, based on an average of one more stoppage per game in the forward half), scoring effectively from kick-ins and playing on after marks more often in the past four weeks as its ball movement quickens. 

Lyon wants Fremantle kicking more and gaining territory but he also wants – as every coach does – his players to show poise in the way they use the football. 

Hayden Ballantyne and Michael Walters make Freo a far more potent force. Picture: AFL Media
Of course, Port Adelaide is a genuine challenger with significant claims to fourth spot based on form in the first 21 games of the season. 

The Power defeated the Dockers by 18 points in round eight at Adelaide Oval but was matched in most of the vital statistics. 

Port faces a Fremantle weakened by Nathan Fyfe's suspension and Michael Barlow's hand injury, as well as doubts over Pavlich after he tweaked a quad in the warm-up on Sunday. 

Port Adelaide's return to form in recent weeks has been impressive too. 

The Power are owning the ball and creating 12.5 more inside 50s than their opposition over the past four games, with notable dominance in that area in the past two games. 

Port Adelaide is also going much wider from its defensive 50, becoming less predictable than the run-and-gun up the corridor tactics that characterised its early good run. 

Port has gone up the corridor 13.9 per cent of the time in the past four games, compared to 21.9 per cent up to round 18. Hinkley's men were heading around the boundary 42.2 per cent of the time up until round 18, but in the past four weeks they have done so 55.2 per cent of the time. 

The return of Jackson Trengove and Alipate Carlile to defence has helped, both inside the defensive 50 and providing flexibility in the ruck, but the team is improving its ability to make quick defensive decisions. 

Even allowing for the wet conditions against Gold Coast, Port is limiting the opposition more in the past month, renewing its focus on defence after conceding 126 points to Richmond in round 20. 

Port Adelaide has been ranked second for points conceded in the past four games, with the Dockers dropping from first – as is common with Lyon-coached teams – to fifth over the same period. 

One team has tightened the screws and the other has loosened them slightly. 

Port Adelaide is tackling less (ranked 16th in the past four weeks after being ranked eighth for tackling differential from rounds 1-18) but winning more uncontested football (from +12 in rounds 1-18 to +44 and ranked No.1) in the past four games.

The Power have also lifted the average amount of time inside their forward half, although it has been ranked No.1 on that measure all season.  

One of the beneficiaries off the ball, spending 17 minutes extra inside the forward half in the past four games, has been Chad Wingard. He has lifted his work rate since the bye and is starting to show signs of a return to form. 

The 21-year-old kicked three goals against Carlton and had 10 score involvements, three above his average this season. It was the first time he had hit 10 since round 14 against the Bulldogs. 

Wingard benefitted from the presence of Angus Monfries and Jake Neade up forward, providing a spark that will inevitably trouble the Dockers. 

The contest is set. Neither side can save anything in the tank for finals. The fourth spot prize is huge. 

No club has won the flag from outside that spot since 2000, when the current final-eight system was introduced. 

"The reality is it's sudden death for the top four next week…they are going to ask some questions of us. We are going to ask some serious questions of them. It's really game on from here, isn't it," Lyon said after the Dockers' win over the Lions on Saturday. 

Two well-coached teams, filled with star players, facing off in a battle for fourth spot. It's hard to split them. 

Now that is the definition of 'game on'. 

Jackson Trengove and Chad Wingard are vital at either end of the ground for Port. Picture: AFL Media