Richmond veteran Nick Vlastuin has been ruled out of the Tigers' season-opener against Carlton, but the news is brighter for top draftee Sam Grlj, who will make his debut.

Vlastuin badly fractured his ankle in the final stages of last season, and has fallen just short of the required conditioning to take to the field.

"We had a plan, knowing that we weren't part of Opening Round, we had two practice games and an intraclub game. So our whole process is around minutes. We've gotten a lot of minutes in our players, we've got the right amount of minutes that we needed," coach Adem Yze told reporters on Wednesday.

"And that's the reason why Nick Vlastuin's not playing this weekend. He just hasn't got that volume of game time leading into Round 1, it would be too high a risk.

"It's just a volume thing right now. He just hasn't done enough. He's had his ankle, and he's had a bit of a grumbly back. He's too important to us to go risking in Round 1. He'll get a really good block of training in now, because obviously we'll have another three sessions before our next game, and he'll be available for Round 2."

Grlj was taken with pick No.8 in the draft from the Oakleigh Chargers, and will inject pace into Richmond's line-up. 

Fellow top pick Sam Cumming (No.7) trained lightly alongside the Round 1 squad on Wednesday, taking some overhead marks without shoulder strapping. The Tigers will give Cumming another few weeks of rehab before assessing whether surgery is required.

"I told (Grlj) today, I was a little bit mindful of telling him too early in a week. He's such an energetic kid, he would have played the game in his head about 20 times, I reckon, if I told him yesterday," Yze said.

"It's great for his family to come along, I think they were Carlton supporters growing up, which is quite ironic. But he deserved his opportunity, we're not going to give games to younger players, he really deserves it. 

"He'll bring a really competitive attitude, his will to win is next level. He swears at the umps out here (at training), which half the time are coaches. He gets really animated because he wants to win. He wants the ball in his hands, and he wants to defend really hard, which is all we can ask of a half-back. He's got some high talent and high speed when he's on offence, but at the same time, his fight to death and the way that he defends is the reason why he's in the team."

With Sydney and Collingwood both utilising the newly opened fifth bench spot as a low-minute, high-impact role (Tom Papley and Scott Pendlebury respectively), Yze opened the door for the Tigers to trial a variety of options in the first few weeks.

"We'll do it differently. Some have used it as a sub, some have used it for a second ruck. But there'll be someone who has lower game time. We'll make that decision, I think that might vary each week," Yze said.

"Whether that's the second ruck, who plays lower game time – we'll probably start that way to help (Toby Nankervis) out, but after that, it will be see how we're going and how the comp's going. It's an unknown, and we'll get a feel for it over the first month of footy."