Emily Fox is not expected to make a quick return to the Arsenal starting lineup this week.

Arsenal will be without Fox for Wednesday’s League Cup semifinal showdown against Manchester United, Gunners manager Renee Slegers confirmed Tuesday. Fox played just 22 minutes in Arsenal’s 2-0 FA Cup victory over Aston Villa on Sunday before leaving the match with an apparent head injury.

Slegers isn’t planning to have Fox available for Wednesday but could have her back as early as this weekend’s league date with Chelsea.

“We assessed her yesterday and today, and we just want to make really good decisions with Foxy,” Slegers said in her prematch press conference Tuesday. “It’s looking likely she won’t be in the squad tomorrow, and then we will assess her again tomorrow and the day after. That’s where we’re at now with Foxy.”

Fox, 27 has made 20 appearances for the Gunners in all competitions, scoring one goal and adding two assists. The veteran defender has continued to hold down the starting right back in North London, but could be replaced by Smilla Holmberg midweek due to her unavailability.

Should Fox miss the next two matches, the next opportunity for her to get back on the field will be on January 31 against Leicester City.