ESSENDON will be the only club allowed to replace players suspended by the AFL Court of Arbitration for Sport with top-up players after an AFL ruling on Friday.

The AFL has told Port Adelaide, Melbourne, St Kilda and the Western Bulldogs their application to replace their suspended players with an extra primary or rookie list player had failed.

AFL general counsel Andrew Dillon said the circumstances did not call for special treatment or exception to the rules beyond those already granted.

He defended the decision to grant Essendon the right to sign up to 10 top-up players.

"An exception has been made for Essendon only because of the sheer number of suspended players it has on its list, and on the basis that they must be able to field a side that that can compete at a basic level each week," Dillon said.  

"If Essendon were not granted list concessions, there may be legitimate health and safety concerns for young and inexperienced players forced to play senior football over a full 22-week season."

AFL.com.au understands that just 14 players since 2000 have played every game of the season in their first season on AFL list.

The four other clubs have been granted permission to upgrade a rookie on to their primary list, but that decision means Port Adelaide – with Angus Monfries and Patrick Ryder receiving season-long bans – may go into the season with one fewer player on their overall list then Essendon.

Under the rules however, the Bombers can only have a maximum of 40 players available for senior selection each week.

Dillon said that every club carried the risk that a player may be suspended after being recruited to a club even though their new club might be an innocent party to the breach that caused the suspension.

Sydney Swans' forward Kurt Tippett was suspended for 11 matches in 2013 after joining the Swans for salary cap breaches that occurred when he was an Adelaide player.

Essendon has signed seven top-up players so far: Ryan Crowley, James Kelly, Matt Dea, Mark Jamar, James Polkinghorne, Jonathan Simpkin and Mathew Stokes.

Port chairman David Koch said his club would accept the decision.

"Obviously we’re disappointed because clearly we are an innocent victim in this saga, and we thought we put together a compelling argument to the AFL," he said.

"However, the AFL saw it differently and we will now abide by their decision and get on with the task at hand. 

"Today’s outcome will not define our season and win, lose or draw it will not serve as an excuse as to how we perform on-field."