It hasn’t often been a pleasant discussion. And this round, a juxtaposition of events involving not just Carlton but two rivals in Fremantle and Adelaide, may make it a little more uncomfortable still.

On Thursday night in Perth, the Blues take on the Dockers - the home side restoring its strength in the ruck with the return of Aaron Sandilands, who has a very handy partner in Zac Clarke. Going up against that formidable duo for Carlton will be Cameron Wood, in his second game of the season, with some help from Levi Casboult.

On Saturday in Adelaide, a former Blue in Sam Jacobs plays his 100th AFL game; he is at the peak of his powers and a serious contender for All-Australian selection.

Meanwhile, on the same afternoon, Robert Warnock, recruited from Fremantle on a handsome deal in 2010, and whose presence forced Jacobs to leave Visy Park a year later in search of a senior game, will be at Cranbourne, doing the ruckwork for VFL side Northern Blues.

Injury has provided Warnock with some pretty low moments in his eight-year AFL career, but he’ll need to be resilient indeed over the next few days not to feel a symbolism more crushing than any other disappointment he’s endured to date.

The club he left nearly six years ago not only managed to overcome his departure, but has never been better off for ruck quality or depth. But even the presence of Sandilands and Clarke wasn’t enough for Carlton select him this week after he had been dropped for the win over North Melbourne.

All while a former colleague effectively downgraded by Warnock’s arrival at Carlton, younger and with two years less AFL experience, reaches the 100-game mark first, commanding a reputation as one of the game’s finest ruckmen.

If there is to be a flashpoint in Warnock’s own career, this surely must be it.

Ruckmen in the modern game can no longer rely merely on the quality of their tap work. Their capacity to take marks and gather possessions around the ground is just as, if not more, important. And in that regard, Warnock’s numbers until his omission a fortnight ago are damning.

In 10 of his 16 games, including his last six, he failed to pick up 10 possessions. He’s taken more than two marks in a game just once all season, and hasn’t succeeded as a forward target, either, with just four goals.

A total of 23 ruckmen have played at least 10 games for their clubs in 2014. Of those, Warnock averages fewer disposals per game than all bar three. His marks per game average of 0.9 is in stark contrast to the likes of Jacobs (4.2), Dean Cox (4), Paddy Ryder (4) and Sandilands (3.8).

That simply isn’t enough to sustain even a dominant tap ruckman, and sadly for Warnock, in 2014 he hasn’t been even that, ranking only 10th for hitouts won and a lowly 21st for percentage of hitouts won to advantage.

It was no great surprise when coach Mick Malthouse’s patience with his No.1 ruckman finally ran out before the game against North Melbourne. But if anything, Warnock’s continued absence despite a strong performance in the VFL last week, not to mention an opposition on Thursday containing Sandilands and Clarke, is an even bigger statement.

It certainly casts a dark cloud over Warnock’s future. The big man was contracted for a further three seasons halfway through 2012, meaning he’s got one more season left on his deal.

With Jacobs long gone, Shaun Hampson leaving for Richmond and Matthew Kreuzer out with a foot injury since round one, 2014 was the year when Warnock could have put any debate about just who was Carlton’s pre-eminent ruckman to bed.

It hasn’t happened. And with Wood, taken in the rookie draft merely as back-up, now a preferred option, and Kreuzer, who offers more flexibility and mobility, at least returning next year, if not this season, for Warnock, the writing could already be on the wall.