The duo now face a number of weeks on the sidelines after suffering injuries in the European Champions Cup win over La Rochelle.
Winger Daly suffered an ankle injury and is now set for 12 weeks on the treatment table.
Hughes also went down in the game and the No.8 is set for a 10-week lay off after suffering damaged knee ligaments.
Neither England man is likely to require an operation, but Young admits it is a blow.
He said: "Elliot has injured his ankle - he has a syndesmosis injury - which is pretty common.
"He is going to see the specialist to see whether any surgical intervention is required which, depending on the grade of the injury, hopefully it won't be.
"Nathan has an MCL injury to his knee. Again, we're waiting on the specialist to let us know what is required, but we can safely say even the best picture, which is a grade one tear, will require a minimum of four weeks."