Aston Villa defender Nathan Baker will miss Saturday's Premier League game against Liverpool at Anfield.
The 22-year-old central defender has been ruled out of the trip to Merseyside after he suffered concussion during the 2-1 defeat to Arsenal at Villa Park on Monday.
Baker was stretchered off on 21 minutes after he was struck in the face by a shot from Arsenal teenager Serge Gnabry.
Villa manager Paul Lambert told his club's official website: "Nathan is still not feeling good.
"He's still feeling a bit groggy with a sore head. He won't be available. Everybody else is pretty good at the minute."
England U21 international Baker has made 15 Premier League appearances for Villa so far this season.
Lambert also revealed that midfielder Chris Herd is set to miss out again at the weekend with a hamstring problem.
However full-back Joe Bennett is back in contention after returning to training following a back injury.
Watch Liverpool take on Aston Villa live on Sky Sports 1HD at 5.30pm on Saturday