Manchester United need to get up and running in the Europa League with victory against Zorya Luhansk, says Jose Mourinho.
United welcome the Ukrainian side to Old Trafford on Thursday desperately seeking their first points in Group A, the Red Devils having lost their opener 1-0 at Feyenoord on matchday one.
Many expected Mourinho to treat the Europa League as secondary to their Premier League exploits, but the United boss is fully focused on progressing in Europe as well.
"It's very important," he told a news conference. "To be honest I think we have to win.
"If we don't win, we have four matches [left in the group] and I would say we have to all the last four matches, which is difficult. We need to win."
Mourinho rested a number of first-team stars for the opening game of the group at De Kuip, but he will change his approach against Zorya, with Zlatan Ibrahimovic and Anthony Martial both included.
He added: "Zlatan starts.
"We have two matches and then he has two weeks without football. For him he just has to play tomorrow and then against Stoke [City on Sunday], then two weeks without football. Zlatan is one of the players who will have plenty of time to recover.
"He [Martial] is now recovered from the contusion - not a concussion. He has recovered and he is ready."
United, though, will be without Luke Shaw and Henrikh Mkhitaryan.
"Luke Shaw is ill. [He has a] temperature, fever, bad throat," said Mourinho on Wednesday. "He arrived this morning and the doctor sent him home.
"[Mkhitaryan] is not playing."