Ralf Rangnick's wait for a work permit means Michael Carrick will remain in charge for Manchester United's match against Arsenal on Thursday.
New interim manager Rangnick arrived in England before new travel restrictions came into effect, but is awaiting a permit before he can start work at United.
United said the visa application process means caretaker boss Carrick will be in the dugout once more, having already overseen the 2-0 win at Villarreal and 1-1 draw with Chelsea after Ole Gunnar Solskjaer was sacked.
"Michael has communicated this to players and staff at Carrington in a busy week for the club," the club said. "Preparation is continuing for the visit of the in-form Gunners."
- Get Sky Sports | Live football on Sky Sports
- Man Utd fixtures | Premier League table
- Man Utd appoint Rangnick as interim manager
Rangnick landed before the new guidelines came into force from Tuesday, which requires individuals to self-isolate until they can provide a negative PCR test that must be taken within 48 hours of arriving in England.
The German was confirmed on Monday as United's interim manager until the end of the season, and his first game in charge is now set to be at home to Crystal Palace on Sunday.
United then have a home Champions League match against Swiss side Young Boys next week, but new rules for individuals returning to Switzerland could see that game moved to a neutral venue.
- Why Ralf Rangnick is in demand
- Paul Merson unconvinced by Ralf Rangnick at Man Utd
- Ralf Rangnick has tools to work with at Man Utd
The 63-year-old's contract will see him take charge of the first team until June and then remain at the club for at least a further two years in a consultancy role.
Sky Sports' Jamie Carragher on Super Sunday:
"I think the appointment of Rangnick will be a positive step in terms of how he wants football played. The top teams in European football, and three of them are in the Premier League, all play the way Rangnick has always wanted his teams to play going back 20 years.
"Top-level football is played like that and Manchester United were a million miles away from that.
"Rangnick is coming in now to make sure that Manchester United get back into the Champions League for next season.
"But Rangnick's biggest job is identifying the next coach. The top people at the club will be taking advice from him. He will want the next coach to be in his image so he'll be almost getting them ready for the next coach and how they want to play."
The story of how the Manchester United-bound Ralf Rangnick helped to revolutionise German football and inspire Jurgen Klopp, Thomas Tuchel and others.
December 2: Arsenal (h) - Premier League, kick-off 8.15pm
December 5: Crystal Palace (h) - Premier League, kick-off 2pm
December 8: Young Boys (h) - Champions League, kick-off 8pm
December 11: Norwich (a) - Premier League, kick-off 5.30pm, live on Sky Sports
Follow every Man Utd game in the Premier League this season with our live blogs on the Sky Sports website and app, and watch match highlights for free shortly after full-time.
Want the Man Utd latest? Bookmark our Man Utd news page, check out Man Utd's fixtures and Man Utd's latest results, watch Man Utd goals and video, keep track of the Premier League table and see which Man Utd games are coming up live on Sky Sports.
Get all this and more - including notifications sent straight to your phone - by downloading the Sky Sports Scores app and setting Man Utd as your favourite team.
Hear the best Premier League reaction and expert analysis with the Essential Football and Gary Neville podcasts, keep up-to-date with our dedicated Transfer Centre, follow the Sky Sports social accounts on Twitter, Instagram and YouTube, and find out how to get Sky Sports.