Warren Gatland has claimed that he will not accept anything less than 100% from his Wales players after they moved closer to a spot in the knockout stage of the World Cup.
A 28-25 victory over England at the weekend was crucial for their hopes of qualifying from Pool A, but progress will still come down to the performances against Fiji and Australia.
After declaring himself disappointed with a training session this week, Gatland insists that no player is safe in the team.
"I said 'if I see any body language or anything that's not right, I will change you'," Gatland told reporters ahead of Thursday's meeting with Fiji.
Despite losing more players to injuries in the win against England, Gatland believes that keeping his men focused could be the biggest challenge.
"You get a massive high from that [England win] and you've got to make sure that sometimes the challenge is not the physical challenge but the mental challenge," he added. "That's our job as coaches to make sure they're ready for that mental challenge."
Tyler Morgan, Alex Cuthbert and Matthew Morgan have come into the team for the game against Fiji in Cardiff.