The Red Devils head into the game fresh from having kicked off their Champions League campaign on a positive note by claiming a 3-0 win at Young Boys on Wednesday night.
Rojo is yet to feature for Manchester United this season after picking up a knee injury while at the World Cup with Argentina, but he is closing in on a return to action.
Herrera, meanwhile, is still on the road to recovery after the Spanish midfielder picked up an ankle injury at the start of the month.
Both players are nearing returns to action, but Mourinho has now confirmed that neither will be fit for Saturday’s clash against Wolves this weekend.
Speaking to MUTV, Mourinho said: “There are small things but nothing important.
“At this moment, Marcos Rojo is not training with the team, but Herrera is in the final phase of his recovery.
“Apart from them [and the suspended players], everyone is ready.”
Marcus Rashford and Nemanja Matic are both unavailable for Saturday’s game due to suspension.
Manchester United are aiming to make it three wins in a row for the first time this season in the Premier League after they lost back to back games against Brighton and Tottenham at the start of the campaign.
Mourinho is aiming to steer the Red Devils towards a Premier League title challenge after they finished second and without a trophy last term.
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