The duo were not ruled out before the match but when the teams were announced for Sunday’s fixture, both players were not named in Mourinho’s matchday XI.
When asked why Rashford and Herrera were missing from United’s squad, Mourinho replied: ‘Injured both.’
Asked if both injuries were long term, Mourinho replied: ‘I don’t think so.
‘But let’s wait a little bit because when it is little tweaks in muscles, you never know until you know for sure.
‘But not possible today.’
United are already without Daley Blind, Marouane Fellaini, Eric Bailly and Zlatan Ibrahimovic, who are all sidelined through injury.
Elsewhere, Paul Pogba has returned to United’s starting XI after he was dropped against Huddersfield last Saturday, while Phil Jones also makes a comeback after missing the 2-0 win at Old Trafford due to illness.
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