In one of the most eye-catching moves of the 2025 AFL Trade Period, St Kilda have secured Tom De Koning as a restricted free agent after Carlton elected not to match. The Blues will receive first-round compensation—currently Pick 9—for allowing him to depart.
Why this deal matters
De Koning is a rare kind of tall: not just physically imposing, but mobile, contested, and capable of influencing multiple phases of the game. At 201 cm, he can roam forward or roll through the ruck, giving definition to what had been a more fixed forward structure for the Saints.
His signing offers St Kilda:
- Dual-role flexibility — With Rowan Marshall already providing ruck strength, De Koning allows Ross Lyon to rotate creatively. He can relieve Marshall, play forward and sink back, or press as a matchup problem.
- Aerial punch + ground craft — De Koning can be a contest monster in the air while also getting involved in second efforts near stoppages.
- Structural balance — Beyond just adding height, this is a move to stabilise the spine, giving clean pathing for midfielders exiting defence and improving inside-50 trajectory options.
Strategy & fit
This isn’t a hiring of a brute; it’s a hiring of a chess piece. The Saints can:
- Use De Koning as a front-half aerial target, forcing defensive attention and creating space for pressure forwards behind him.
- Rotate him in ruck contests (especially late in games) to protect Marshall or exploit matchups.
- Vary entries to reduce predictability—sometimes over the top, sometimes hitting the corridor with direct kick-ins.
Defenders will have to account for a second tall; mids will trust delivery more. Having two legitimate weapons means structures can stretch wider, and stoppage setups become more nuanced.
List and cap implications
St Kilda have been active this trade period, and opting to use a free agent acquisition rather than a heavy picks trade shows bold list planning. The compensation pick they part with is steep, but the move is a direct injection into the core of the club.
MELBOURNE, AUSTRALIA – AUGUST 21: Patrick Cripps (left) and Tom De Koning of the Blues celebrate during the 2025 AFL Round 24 match between the Essendon Bombers and the Carlton Blues at the Melbourne Cricket Ground on August 21, 2025 in Melbourne, Australia. (Photo by Michael Willson/AFL Photos via Getty Images)
The bottom line
This is a pure upgrade, not a lateral shake. De Koning doesn’t simply add depth—he reshapes how St Kilda can build inside-50s and manage their forward/ruck balance. The Saints’ trajectory just got steeper.
