IF YOU listen to recent critics of the AFL's medical substitute rule, the innovation brought in at the start of the 2021 season has become a loophole ripe to be exploited by savvy clubs desperate for a late-game injection of fresh legs. 

But what do the numbers tell us? 

An analysis of the medical substitutes made in 2022 shows that of the 63 substitutes made between rounds 1-6, 22 per cent (or 14 players) have played the following week, despite being ruled unfit at the time of substitution.

That's an increase on 2021's overall numbers, where 14.5 per cent of the 186 substitutes played the next game (within 12 days, so discounting pre-bye or end-of-season matches).

Medical subs made in 2022

But a further breakdown of this year's numbers shows the rate of players returning the following week is dropping as the season goes on. In the first three rounds, 28 per cent of players who were substituted out returned the following week, but that figure dropped to 16 per cent between rounds 4-6. 

If that trend continues, the final overall figure will end up close to the 2021 figure of 14.5 per cent.  

So despite the dialogue of late, there hasn't been a rapid increase in subs returning the following match in recent weeks, and it's actually heading in the opposite direction.

MEDICAL ROOM Check out the full injury list

Three of Port Adelaide's six subbed-out players have been fielded the following week – the most of any club – with Xavier Duursma (collarbone), Trent McKenzie (ankle) and Robbie Gray (knee) all backing up.

Gold Coast (Jy Farrar, hamstring and Mabior Chol, adductor) and Hawthorn (Chad Wingard, hamstring and Jack Scrimshaw, collarbone) have each fielded two players the week after they were substituted.

Of the players substituted in the round just gone, Max Holmes (syndesmosis), Brodie Smith (concussion), Miller Bergman (shoulder), Joe Daniher (shoulder), Willie Rioli (hamstring), Liam Stocker (shoulder) and Joel Smith (ankle) have already been ruled out for this weekend.

It remains to be seen if Dion Prestia (ankle), Conor Nash (ankle), Mitch Georgiades (calf), Connor Budarick (ankle), Mitch Wallis (foot), Nik Cox (calf) and Harry Cunningham (abdomen) play.

Fremantle, GWS, St Kilda and Collingwood did not activate their subs.

The medical substitute rule was first introduced at the start of the 2021 season. Initially envisioned as a concussion substitute in its planning stage, it was extended to cover all injuries and illness. 

It's effectively a fifth – and permanent – interchange, with one player from the four emergencies warming the bench until a teammate is ruled unfit to continue by the club doctor.

In the days of the green/red vest substitutes (2011-2015), rucks and tall forwards were often brought off at three-quarter time and a smaller running player introduced, to provide some spark to a tiring outfit.

Of the 14 substitutes who have played the following week, only Jeremy Cameron, Darcy Cameron and Mabior Chol fit into that category, and Cameron was taken to hospital following his collision.