Grayson has been consistent with his squad selection during pre-season, but insists there are still places up for grabs.
"Everyone will have been looking to see if that was the team against Wolves, but everyone is playing for their places," Grayson told the club's official website.
"That's all across the pitch. No position is set in stone. Everyone has to be ready to start.
"There are many occasions where players don't start in the first game, but know that within a couple of games there will be an opportunity.Players will be looking to impress in training this week."
Source: PA
Source: PA