Edinson Cavani and Harry Maguire have not travelled with the Manchester United squad for their Champions League opener against Paris Saint-Germain.
Cavani, 33, only started training with his new teammates on Sunday after quarantining for two weeks following his deadline day signing. The Uruguayan has not played a competitive match since PSG beat Borussia Dortmund on March 11.
Maguire was deemed a doubt for the Saturday night trip to Newcastle but started and scored United's equaliser in their 4-1 win. Maguire and Cavani were absent when the United squad arrived at Manchester Airport on Monday afternoon.
Mason Greenwood was also missing from the flight after he sat out the Newcastle win with an unspecified injury, while Jesse Lingard and Eric Bailly are also out. United have included Facundo Pellistri in their squad to face Paris Saint-Germain.
New signing Pellistri, 18, was included in United's Champions League squad and the Uruguayan is in contention to make his debut in their group stage opener at the Parc des Princes.
United signed right winger Pellistri for £9million from Penarol on deadline day and manager Ole Gunnar Solskjaer suggested last week he was one for the future.
"We're looking forward to integrating them into the group," Solskjaer said. "Facundo has been in training with us two days, very exciting, young, enthusiastic player with some attributes we don't have. He's maybe one for the future, maybe not for just now, still only 18."
Recent arrival Alex Telles - on the bench at Newcastle on Saturday - has also flown with the United squad to the French capital.
Solskjaer can name 12 substitutes in the Champions League this season and make up to five substitutions.
Confirmed United squad members
David de Gea, Dean Henderson, Aaron Wan-Bissaka, Timothy Fosu-Mensah, Axel Tuanzebe, Victor Lindelof, Luke Shaw, Alex Telles, Brandon Williams, Paul Pogba, Scott McTominay, Bruno Fernandes, Fred, Nemanja Matic, Donny van de Beek, Facundo Pellistri, Daniel James, Juan Mata, Marcus Rashford, Anthony Martial, Odion Ighalo
