ROUND one saw the return of the tactical substitute, and coaches had plenty to consider as to when to pull the trigger, and who to unleash on the game.

Replacing the two-season medical substitute, the tactical sub was last used in 2015, when the fourth player on the bench was given the dreaded green or red vest. This year, the sub is pulled from the emergencies as a fifth bench player, named an hour out from the bounce.

Generally speaking, the third term was the most popular time to make the change, while talls were more likely – but only just – to be pulled from the game.

Brisbane, Sydney, Essendon and Fremantle waited until the fourth quarter was underway before making their substitution, with the Swans and Bombers ultimately winning their matches.

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St Kilda coach Ross Lyon may have been ruing flicking the switch on the sub halfway during the third term, with Jimmy Webster injuring his leg just minutes later.

"I think I've used a tactical sub before (from 2011-2015), but we talked about it – often it'll be through injury, and you'll use it, but if you get the luxury … we activated just before three-quarter time.

"But then you see Banfield come on, fresh legs, and your backs are tired, and that's dangerous. So you try and manipulate your freshest (onto theirs), that's why Paton rolled back to the back six for most of the last quarter. He gave us some fresh legs to handle what they were throwing at us there.

"We'll probably consider it a little bit longer (next time), it's a really good point. Damned if you do, damned if you don't."

Unsurprisingly, clubs opted for versatile, running players as their sub – who can theoretically slot in across all three lines and provide some spark – while medium forwards also emerged as a popular category. No key position players were used as starting subs.

Five players – Tom Stewart, Jeremy Howe, Tristan Xerri, Liam Jones and Harry Perryman – were forced injury substitutions

Taller players were the preferred unforced substitutions, with seven key defenders/forwards/rucks sent to the back of the dugout, compared to six shorter players.

Of those six, two were debutants (Lachie Cowan and Bailey Laurie), while James Tunstill was playing his fourth AFL game.

Richmond had earmarked the underdone Marlion Pickett as the player taken off before the game began.

"He is the guy we looked at, and we ummed and ahhed, but he's a big-game player, Marlion. We love his physicality, and the plan was always to play two and a half quarters, then Jack Ross would come in," coach Damien Hardwick said.

"It was just one of those ones where Marlion is going to get better the longer the season goes on. He's had a little bit of an injury-interrupted pre-season, but once again, you take a little bit of a risk, hoping no one gets injured, but we got through and so we were able to pull the lever on the sub."

Hardwick's counterpart on Thursday night, Michael Voss, had the luxury of a purely tactical sub, removing debutant Cowan from the game at three-quarter time for Lochie O'Brien.

"I thought it was more efficient (than the medical sub), it was absolutely more efficient. It does open up that conversation as to what you want to do, and what's the area of the game you want to go after a little bit more," Voss said.

"Obviously we had Lochie O'Brien, and that was a fair race down the wing there, so some fresh legs just to finish the game off.

"You could use it for those particular moments, but I think coaches will go to work on that. And I think when you use it is probably just as important as to who the sub is at that time."