Fremantle have deemed Alex Silvagni as the player to fill a worrying gap in defence as the Dockers headed east for Saturday's elimination final with Geelong at the MCG.
But in a shock move the port club has left Jon Griffin out of the squad that departed Perth today.
Dockers assistant coach Mark Stone said the prospect of rain in Melbourne at the weekend prompted the match committee to opt for a smaller, more versatile back-up for No.1 big man Aaron Sandilands.
As a result utility player Kepler Bradley was included in the 25-man squad that boarded the plane.
"We'll take the full squad to cover all bases and in case anything happens between now and the game," Stone said.
"We have got (Kepler) and Zac in the squad and at this stage he (Bradley) he is likely to come into the side.
"It is unfortunate for Jon. There is a chance of a shower and it is a night game so we don't want to get caught too big."
Midfielder Matt de Boer, ruckman Zac Clarke, defender Dylan Roberton and youngster Cam Sutcliffe were also in the travelling party.
Clarke, Roberton and Sutcliffe are expected to be the emergencies when the team is formally announced later this afternoon.
Silvagni was tipped to be the replacement for injured backman Luke McPharlin, who damaged a hamstring in the win over Melbourne last Saturday.
The 24-year-old has played just four matches this season but he was preferred to retiring veteran Antoni Grover as McPharlin's replacement.
The pair have spent much of the training week working off each other in an attempt to prove they could cover for McPharlin.
Stone said Silvagni was expected to come into the side for the first time this season since the round 14 clash with Collingwood.
Bradley could also be called on to pinch-hit in the backline as the Dockers try to counter a Cats line-up with plenty of forward options.
The 26-year-old missed the battle with the Demons because of concussion.
Teammate Ryan Crowley tweeted a picture of Bradley enjoying some extra room in business class on the flight.