(Image: Twitter)

Once it's on the Internet...

Fremantle has deleted a tweet on Thursday arvo that prematurely announced a debutant for this week.

The tweet was posted at 4:30, and was up for around 5-10 minutes before it got swiftly removed.

It announced defender Brennan Cox was to make his debut against Brisbane this week.

"Debutant @Brennan_Cox36 getting use to the @VirginAustralia Lounge perks!" it read.

Sneaky stuff from the Dockers!

Cox has impressed down back this year, averaging 15.4 disposals and 6.6 marks a game.

He was drafted last year with pick 41.