RICHMOND forward Tyrone Vickery will miss this week's NAB Challenge game against Hawthorn after being concussed.
Vickery was hurt in last Friday's game against Fremantle. Worrying footage was first uncovered by AFL.com.au on Monday of the 25-year-old going for a mark in the forward line, despite the ball more than 50 metres away
The Tigers aren't sure when he was injured but suspect it may have happened before the game.
"We heard that he might have got a knock in the warm-up. There's no vision of that to show if it did happen," Richmond stand-in coach Brendon Lade said.
"Ty's been in at the club all week. The doctors sent him off for some tests. He's fine at the moment.
"He'll have a week off… and be ready to go the week after hopefully."
Vickery trained on Thursday but avoided contact drills. He completed light exercises on the boundary before the session began.
Captain Trent Cotchin, Dustin Martin and Jack Riewoldt also trained fully on Thursday and will begin their 2016 campaign in this Saturday's game against the Hawks.
Brett Deledio will miss but should be back for Richmond's final NAB Challenge game against Port Adelaide on Thursday, March 10.
The 28-year-old has been struggling with a persistent Achilles injury. He ran laps at training with Nathan Drummond, who is recovering from a knee reconstruction.
With the interchange cap dropping from 120 to 90 for the upcoming season, Lade said the Tigers were using the NAB Challenge games to train the players' endurance.
"Last week we only had 82 rotations. We were really keen to get… the boys' fitness right up.
"We've adjusted our training accordingly through the pre-season. We'll keep trying to go with 90 rotations for the next two weeks."
Richmond played a relatively weak line-up against the Dockers but Lade said that was in line with how the Tigers think practice matches should be structured.
"As a club, two games is probably perfect going into round one, and that's what we're aiming for," he said.