United face Sevilla in the first leg of their Champions League round-of-16 tie on Wednesday followed by Chelsea's visit to Old Trafford on Sunday.

Mourinho said he took every available first-team player to Huddersfield Town for the FA Cup fifth-round tie on Saturday and was forced to supplement the squad with youngsters Ethan Hamilton and Angel Gomes.

Marcus Rashford, Ander Herrera, Marcos Rojo, Phil Jones, Antonio Valencia, Daley Blind, Marouane Fellaini and Zlatan Ibrahimovic were all ruled out with injuries and Paul Pogba was struck down with illness.

"I didn't rest one single player so we had today every player available here," Mourinho said after the 2-0 win over Huddersfield at the John Smith's Stadium.

"I didn't rest anyone. I brought two kids that played on Friday 90 minutes [for the under-23s] because I don't have another player, so we arrive at this crucial moment with some problems."

Jose Mourinho during Manchester United's FA Cup win against Huddersfield. Photo by Chris Brunskill Ltd/Getty Images

Mourinho is hopeful Rashford, Herrera and Valencia will recover in time to make the trip to Spain on Tuesday.

The squad is scheduled to train at Carrington on Tuesday morning before flying out in the afternoon.

However, the United manager admitted Jones and Rojo are unlikely to be fit, leaving Chris Smalling, Victor Lindelof and Eric Bailly, who returned against Huddersfield after three and a half months out with an ankle problem, as his only fit senior centre-backs.

"Can we recover some of them to Wednesday? I believe so," Mourinho said. "I think Rashford, Herrera, Valencia -- I think they have a chance.

"Paul, I don't know. Marco Rojo, Phil Jones, Marouane, Zlatan -- I don't think they have any chance."

United will hope earn a positive result in Spain this week ahead of the second leg at Old Trafford on March 13.

The meeting with Chelsea four days later has also taken on greater significance after two defeats in United's last three Premier League games.

Victory for Antonio Conte's side would move them level on points with United with just 10 games remaining.

"You know, I think mentality is very important," Mourinho said. "And we have strong team strong bonding, strong team mentality. We know it is a very difficult match but we go for it."