Adelaide ruckman Reilly O'Brien has labelled Nic Naitanui "lazy and unfit" in game notes before claiming he mistakenly posted it on social media.
Ahead of his duel against the West Coast star on Saturday, O'Brien posted on Twitter: "Run off him hard.
‘NEVER COME BACK’: Eddie McGuire walks off set after grilling
DISGUSTING: Ablett family targeted after son's diagnosis
‘He is lazy and unfit, will have a field day getting ball and marking everything.
“Get to front and have grunt around the ground, and get ball on deck, beat him in this area.”
But O'Brien soon deleted the post and replaced it with a video, saying: "I have had an absolute 'mare on my social media today, tweeted some of my game notes."
“I take these notes every week before the game to try and pump myself up and give myself confidence.
“I am coming, this week, against who I think is probably the best ruckman in the competition, Nic Nat, and I was just trying to get some confidence.
“I have put pressure on myself now, so I really have to walk-the-walk this week.”
O'Brien is usually renowned for his intelligence - he recorded an ATAR score of 99.75 in year 12 at school and is studying a university degree in biomedicine.
But the 24-year-old's bungle is certain to further motivate Naitanui, a 171-game veteran and All Australian who is averaging 32 hitouts and 12 disposals a match this season.
O'Brien, recruited by the Crows from Victoria in the 2015 rookie draft, averages 25 hitouts and 13 disposals this year.