Brendan Rodgers has given his backing to the tranfer window shutting before the season starts - but only if it done by all leagues.
The Celtic manager was speaking after English Premier League clubs agreed to close the summer window on the day before the start of the 2018-19 season.
The decision came despite opposition from Manchester United and Manchester City, and means clubs will not be allowed to register any new players after 5pm on Thursday, August 9, 2018.
The SFFL has no plans to follow suit and this could cause problems, according to Rodgers.
“My view is pretty clear,” the Celtic manager said. “It’s fine as long as it’s across the board. It should be closed when teams are playing their first games of the season.
“We saw it even at the weekend. Players that were not supposed to be fit to play, all of a sudden make great returns for their national teams.
“There are moral and business issues. Players have maybe been advised, maybe the clubs are protecting an asset if they want to sell them.
“For me, it’s about the inner sanctuary of the dressing room. It’s difficult being in that situation. As a manager you are unsure if they are going to be here or not.
“It’s tough. If you are a coach or manager you would want the window to be shut for that first game of the season.
“But it has to be as aligned as possible.”