AN EMERGING ruck bull in the mould of Shane Mumford was all the rage at North Melbourne last year, coinciding with the struggles of the Roos' All Australian incumbent.

Braydon Preuss was considered so ready for regular AFL football that coach Brad Scott fielded weekly questions about how he could fit both Preuss and Todd Goldstein in the same side.

Preuss, who turns 23 in June, ended up playing the first four games of last year in the AFL and then the final four – and there was some rival club interest in the trade period.

The rugby league convert stayed at Arden St, but is wallowing in the VFL and not forming a strong case for promotion despite Goldstein's performances plumbing nine-year depths.

Goldstein, the game's premier big man in 2015, revealed on season eve he contemplated quitting last year, but rid of his debilitating personal issues he was ready to return to his brilliant best.

He showed signs of a resurgence in his return to the senior side in the final rounds of 2017 after a fortnight back in state league ranks.

But Goldstein has instead gone backwards, highlighted by a caning from Melbourne's Max Gawn, the man who succeeded the Kangaroo as the All Australian ruckman in 2016.

That Gawn whipping resulted in Scott having "upfront discussions" on what Goldstein needed to work on.

Goldy's 2018 by the numbers

Rival ruckmen Brodie Grundy and Stefan Martin average 20-plus possessions and are like extra midfielders, whereas Goldstein wins only half that – and racked up eight in each of the past two weeks.

A former ruckman, who spoke to AFL.com.au on the condition of anonymity, said Goldstein needed to consider new ways to challenge himself.

His suggestion was for the North star to "chase" a great ruckman's feats as his benchmark rather than focus on returning to his old heights.

"For mine, he's plateaued because he's reached that All Australian status, and you go, 'OK, what else are you chasing, where is the new challenge?'," the source said.

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"Why did Jonathan Brown become a good player? Because he was chasing Wayne Carey. It's about giving yourself those challenges.

"This is definitely not a slight on Goldy not being motivated, because that's far from the truth. We're talking about a guy who worked his arse off to get where he did.

"Goldy's come from so far back when he first started that he got sent away from training, but he's got everything at his disposal – it's just a matter of going, 'How can I readjust the way I'm thinking about my footy?'"

He also told AFL.com.au that he saw none of Goldstein's trademark "high-end bursts" in his ground coverage in Sunday's loss to Richmond.

"I don't know whether the outside pressures are affecting him, but how does he get back to playing with freedom, hunting the footy and utilising his best strengths, which are his fitness and ability to move around the ground?"

The same source defended Preuss' drop-off, saying it would be difficult to remain motivated playing in "far-flung places" without knowing when your next AFL opportunity would come.

Another option for the Kangaroos is to redeploy Majak Daw as a ruckman, although they are experimenting with turning him into a defender.

First-year big man Tristan Xerri has impressed in the VFL and amassed 15 disposals, eight marks, three tackles, 11 hit-outs and three goals backing up Preuss at the weekend.

Plenty is going right for North this year, but the ruck division – new part-time coach Will Minson's domain – remains a riddle yet to be solved.

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