The AFL has secretly trialled the use of zones in a clandestine joint venture with St Kilda which took place last week at Seaford.

The training session, overseen by the game's football supremo Mark Evans, is believed to be part of a strategy which would radically ease on field congestion. The training session, which was attended by Evans and umpires boss Hayden Kennedy, has raised questions about what plans league headquarters has for future trials. The zones – similar to those used in the TAC Cup – requires each team to have a certain number of backs and forwards inside the forward 50s at a stoppage.

Is a St Kilda training session a sign of things to come? Credit:Getty Images

It meant that the likes Paddy McCartin, Josh Bruce, Jake Carlisle and Nathan Brown had their work cut out for them during the two ten-minute halves. The first half saw umpires forcing two pairs of players back inside the arcs and the second half trialled three pairs.

"The AFL just wanted to trial it and see what it could possibly look like," Umpires boss Hayden Kennedy told Fairfax Media. "It just happened to fit in with (the Saints) training program.