FRIDAY night could go some way to solving the 'De Koning Debate'.

The subject of a very public long-term free agency offer worth around $1.7 million per season from St Kilda, while entertaining a seven-year deal on significantly less money to remain at Carlton, Tom De Koning's performances haven't been hurt by the intense scrutiny and attention around his signature.

While the athletic ruck's decision has long been a choice between cash and commitment – De Koning could leave more than $4 million on the table, should he opt to shun the Saints and stay with the Blues – the trajectory of both teams has also weighed into his call.

Carlton, a premiership fancy to start the year, has been dragged back into the pack following a disappointing 3-5 start to the season. St Kilda, a side looking to supercharge a young and ambitious rebuild, has shown glimpses of potential amid a promising opening that has yielded a 4-4 record.

In a Friday night clash that symbolically will be worth more than just the four premiership points, both the Saints and the Blues will look to provide De Koning with a demonstration of their trajectory. For the 25-year-old, it could go some way to deciphering the value of staying against going.

But for both teams, De Koning's own upcoming performance at the MCG could help determine the value of a ruck in the modern game. He might be among the game's best in his position, but what does that mean for a successful side?

According to Champion Data's AFL Player Ratings points – the stats guru's most definitive metric to evaluate influence – De Koning has been the fifth-best player in the competition this season and the second-best ruck, behind only North Melbourne's Tristan Xerri.

De Koning's profile stems from his mobility and his ability to act as Carlton's fourth centre-bounce midfielder. He rates 'elite' among rucks for disposals (19.5), contested possessions (12.6), clearances (5.5) and intercept marks (1.6) this year. As for his genuine craft, he ranks fifth in AFL Player Ratings points for ruck work.

But it's through those areas where De Koning has helped Carlton. According to Champion Data, the Blues have a centre-bounce clearance differential of +16 when De Koning is involved. St Kilda's centre-bounce differential lags behind at -9 when the Saints are playing Rowan Marshall.

Champion Data's models also show Carlton being a superior side than St Kilda for hitouts-to-advantage, first possessions and clearances, while being better in transition both offensively and defensively. Again, while that's not solely down to De Koning's influence, a good ruck target and ruck interceptor certainly helps.

Clearly, if you were to swap the colours of De Koning's jumper, St Kilda would improve in such metrics and Carlton would deteriorate. But is that worth the differential in valuations between the two clubs, which sits at around $600,000 per year? Opinions across the industry, as they almost always do with rucks, wildly differ.

Yes, De Koning (who averages 16.0 AFL Player Ratings points per game) is the second highest-rated ruck in the League this season. He sits behind Xerri (17.0) and fractionally ahead of Melbourne's Max Gawn (15.9) and Richmond's Toby Nankervis (15.4).

The common theme among those players, who make up the four highest-rated rucks through the campaign's first eight rounds? They represent teams that boast a collective win-loss record of 9-23 so far. Meanwhile, they play for sides that currently sit 13th, 15th, 16th and 17th on the AFL Ladder.

It's a trait that's weaved throughout recent history. Of the last 14 premiership rucks, Gawn in 2021 is the only one to have made an All-Australian squad – let alone the team itself – in the same season he won the flag.

Gawn himself, perhaps the best ruck in the game's history, is also evidence of how you can grab and develop players for that position from virtually anywhere. He was recruited to the Demons with pick No.34 and played just four games in his first three seasons before blossoming into the footballer he has become.

Brisbane's Oscar McInerney – who rucked for the overwhelming majority of its premiership campaign last season – was a rookie pick. Collingwood only had to slide from pick No.56 to No.62 to snare its 2023 flag-winning ruck Darcy Cameron. Richmond parted with only pick No.46 for three-time premiership ruck and captain Nankervis.

Xerri, the highest-rated ruck in the League so far this season, was brought to North Melbourne with pick No.72. Like Gawn, he managed only four appearances in his first three years on the club's list, but has eventually emerged to become one of the competition's best.

It makes the 'De Koning Debate' a complicated one. While his individual numbers paint the picture of a player well worth a $1.7 million contract, recent history has been evidence that you can compete with cut-price options in that position. Is any ruck, even one as good as De Koning, worth that money?

And, for a side like Carlton – which doesn't have a first-round pick, having traded out of the 2025 pool to help snare Jagga Smith with the No.3 selection last year – is there a serious thought of letting De Koning leave in the knowledge that the free agency compensation will certainly generate an early draft pick?

It makes Friday night's contest an intriguing one. How much will De Koning's performance – which, on the evidence of the season so far, is bound to be a good one – influence the final result? The answer could go some way to helping determine the value of a ruck, and especially one as influential as 'TDK'.