Arsenal have lost their appeal to have David Luiz's red card against Wolves overturned.
Luiz was dismissed by referee Craig Pawson after conceding a penalty for a trip on Willian Jose which allowed Ruben Neves to level, before a stunning strike from Joao Moutinho gave the home side a 2-1 win at Molineux.
What little contact there was appeared to be accidental, but the Football Association have told the Gunners that the decision will stand.
"We have worked really hard to overturn David Luiz's red card," the club said in a statement on their website.
"We presented our case to the FA but are disappointed that our appeal has been unsuccessful. We accept the FA's decision and continue our preparations for Saturday's match against Aston Villa."
Southampton enjoyed more luck with the FA on Thursday after an independent regulatory commission upheld a claim of wrongful dismissal of defender Jan Bednarek.
Bednarek was sent off for a challenge on Anthony Martial in Manchester United's 9-0 win over the Saints on Tuesday, with referee Mike Dean sticking with his initial decision after being invited to check the pitchside monitor at Old Trafford.
Bednarek will now be available for Southampton's trip to Newcastle United on Saturday.