Matic was replaced by Ander Herrera midway through the second half during Wednesday's 4-2 win at Watford after limping off.
The Serb, who is believed to be carrying a muscular injury, will travel with the squad to north London for Saturday's evening kick-off before a decision is made on his involvement.
“Matic is a doubt. I hope he can but I cannot guarantee,” Mourinho said.
“He is selected to go. Let's see the feeling before the match, let's see the warm-up. I hope he can, I want him to, he wants to but I cannot guarantee.”
Mourinho will be unable to call upon Marouane Fellaini as a replacement. The Belgian will not travel with the squad to Arsenal having also missed Wednesday's win at Vicarage Road.
If Matic does not play, Herrera is likely to fill in alongside Paul Pogba in midfield. Long-term absentees Phil Jones and Eric Bailly remain unavailable.
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