NICK RIEWOLDT'S march towards the all-time marks record has been delayed by a statistical anomaly that has only just come to light.

There has been recent commentary about the St Kilda champion closing in on the longtime record set by Footscray and North Melbourne ruckman Gary Dempsey.

Riewoldt was believed to be within five marks of Dempsey's supposed tally of 2906 – an effort the 34-year-old would have been expected to pass against Richmond at Etihad Stadium on Saturday night.

It would have been a fitting occasion to achieve the feat, given the 'Maddie's Match' charity clash pays tribute to Riewoldt's late sister, who died two years ago from a bone marrow failure syndrome called aplastic anaemia.

However, Col Hutchinson – the AFL's statistics and history consultant – has discovered that Riewoldt will take a little longer than anticipated to claim the record because Dempsey's tally is incomplete.

Hutchinson has found that one Dempsey performance remains unaccounted for.

The game in question was between the Bulldogs and Carlton at Princes Park in round 11, 1975 – a game Dempsey's Dogs lost by 12 points.

It seems the stats were recorded but weren't published in any newspaper, and Hutchinson suspects it had something to do with the fact the entire round of matches was played on a Monday – a Queen's Birthday public holiday.

What we do know is that Dempsey, then 26, had been in such superb form that he'd win that season's Brownlow Medal and the fourth of his seven club best and fairests.

Dempsey likely took a swag of grabs that day at Carlton, given The Age rated him the fourth-best Bulldog and his tallies in the previous three games had been 14, 13 and 13. He also took 16 marks the week after.

In his 20 documented games that season Dempsey averaged 10.3 marks, and hauled in at least 11 grabs on 11 separate occasions.

It's logical to assume Dempsey would have taken somewhere between 10 and 16 marks in the mystery match, bumping his career tally up to the vicinity of 2916-2922.

So Riewoldt still needs 22 marks before we can comfortably crown him as the game's most prolific markologist (since weekly statistics were first recorded in 1965).

If you can solve this stats mystery, please email ben.collins@afl.com.au. 

Most marks - 1965-2017

* statistics from one game are unknown