Manchester United boss Louis van Gaal says his biggest concern after yesterday's defeat at Arsenal is that key players will leave for international duty.
The Red Devils suffered their second defeat of the season, a 3-0 away defeat at the Emirates.
And the Dutchman says it will not be easy for his players to bounce back after they return from international duty.
"My biggest concern is that the players are flying out from London," van Gaal said.
"They have to go to their national teams, so we cannot prepare for the match against Everton. I have to wait to see if the players are fit enough but also mentally fit enough to play.
"We cannot train because they are coming back on Wednesday and Thursday, so it is much better to win and then you can prepare the next game.
"Before the last international break we lost against Swansea City, but we won against Liverpool after it, so we can do it, but today was a shock for me."