The Bulldogs and Fremantle face off at Marvel Stadium on Sunday, with a finals spot on the line.
But first, there was room for some amusing scenes.
About 30 minutes into Friday's training session at Whitten Oval, Bulldogs coaching staff became aware of Dockers ruck and development coach Naismith sitting in the fourth row of the stands.
The Bulldogs' media team was made aware of the former Richmond and Sydney ruckman's presence, while coaching staff moved to remove him from the ground.
Western Bulldogs assistant coach Daniel Pratt left the oval and walked up the stairs to give Naismith his marching orders.
Shortly after, Naismith, coffee in hand, and his companion departed.
Naismith was wearing all black, including a black cap, and was holding a coffee but made no other effort to disguise himself.
The long-haired, 206cm former ruckman, who retired last year after an interrupted career ravaged by ACL injuries, is a surprising and unconventional spy of choice, given his large, recognisable frame.
It's not the first time spying has happened in the AFL.
Fremantle previously were caught out for spying on a Port Adelaide training session back in 2015.
Perhaps the best-known example of 'Spygate' in sport was when former Leeds manager Marcelo Bielsa was caught spying on rivals Derby County in 2019.
Bielsa later admitted he had spied on all of Leeds' opponents, famously detailing his tactics in an hour-long PowerPoint presentation to journalists.
This week, Fremantle coach Justin Longmuir insisted the pressure was on the Bulldogs.
Bulldogs coach Luke Beveridge, who spoke before the amusing spy drama, wasn't buying into it.
"I'm not that interested in the tit-for-tat on that," he said.
"The equation's simple.
"Both clubs are in the same situation: you win or you're out."
14°C