United face a must win match in their second Europa League group game after losing to Feyenoord in the opener.
And Jose Mourinho has confirmed Ibrahimovic will start the match but he still harbours doubts over Wayne Rooney.
The club captain was dropped for the 4-0 win over Leicester on Saturday and could be set for an extended run on the sidelines.
Related articles
- Rashford: How Ibrahimovic has helped me since joining Man United
- Jose Mourinho confirms Zlatan Ibrahimovic's role against Zorya
"Zlatan starts,” Mourinho said.
However, he thinks bringing Rooney back into the side could be dangerous.
“I was completely convinced of playing him tomorrow,” he added.
“I’m not sure if I do that because with the situation that you create to him I think he really can’t afford to have a performance that is not really good and I am here to protect him and have to analyse the best thing for him.
“If he is not totally ready for it, I will discuss that with the medical staff.”
Related videos
- Manchester United and Feyenoord hooligans clash in 1997
- Manchester United vs FC Zorya - Europa League match preview
- Hilarious Manchester United player mocks teammates
And midfielder Jesse Lingard admits Ibrahimovic has been leading the side in Rooney's absence.
“He’s been a leader for the team, especially when the captain’s not playing," said Lingard.
"He’s stepped up and he’s really led the team. Obviously the young lads look up to him and most of the older ones do as well.
“When you see the things he’s done in his career [you can’t help but be impressed].”
He added: “He helps the young lads a lot. Especially me and Marcus [Rashford].
“He’s always there for us and always there for the team.”