THIS year's free agency crop is the oldest in recent years and lacks depth in the 25-26 age bracket that has proved far and away the happiest hunting ground for rival teams.

A remarkable 25 of the 37 players – 67.6 per cent – who have moved clubs since free agency's introduction in 2012 have been aged 25 or 26 at the start of the relevant season.

AFL.com.au has compiled a preliminary list of 2019's free agents, which reveals a distinct lack of targets in this player movement sweet spot.

The decision of Nick Haynes, 26, to re-sign with Greater Western Sydney on Friday means just 15 of 2019's 67 eligible free agents will be 25 or 26 when the premiership season kicks off on March 21.

Although there is undeniable quality among this crucial age bracket, which includes Stephen Coniglio, Adam Tomlinson, Jack Newnes, Tom Liberatore and Sam Day, it accounts for just 22.4 per cent of this year's total pool.

This is a significant drop from the past two years, when players aged 25 or 26 at the start of the season accounted for:

31.4 per cent of the free agency pool – 16 of 51 players – in 2018; and
31.7 per cent – 19 of 60 players – in 2017.

This drop can be partially explained by a frantic last day of the 2018 trade period, when prospective 2019 free agents Dylan Shiel, now 26, Chad Wingard and Lachie Neale, both 25, were traded.

Greater Western Sydney, Port Adelaide and Fremantle were prepared to agree to their respective player's trade request, confident they could broker better returns than if they waited another year for free agency compensation.

Meanwhile, more than half of 2019's existing free agents will be 30 or older as of round one, casting further doubt on how active this sector of the player movement market will be.

Just two free agents aged 30 or older have changed clubs – Jarrad Waite (2014) and Daniel Wells (2016), who were both 31 at the time – and this year's crop includes a whopping 35 such veterans, who represent 52.2 per cent of the total pool.

This is a significant spike on last year when just 35.3 per cent of the players on the AFL's official free agency list were 30 or older – 18 of 51 players.

In 2017, 45 per cent of free agents – 27 of 60 players – were 30 or older at the start of the season.

Hawthorn has the most 30-year-olds on this year's list with five, Sydney has four, while Adelaide, Fremantle, Richmond, West Coast and the Western Bulldogs each have three.