Aston Villa striker Chris Sutton will soon find out if he can play again after undergoing a third set of tests to examine his blurred vision.
Sutton joined Villa in October 2006
Sutton has been out since December but boss Martin O'Neill said: "They should give us some sort of conclusions.
"If someone could guarantee that if Chris took another knock on the head and it wouldn't do him any harm, then he would be fine.
"But no-one is in a position to guarantee that just at the moment."
The 33-year-old, who is out of contract with Villa at the end of the season, sustained the injury against Manchester United on 23 December.
And O'Neill added: "His vision is not improving greatly.
"He can do normal things but the concern is if he got hit again and it worsens.
"Chris is going to start non-contact stuff with us. It has been a really slow process, a really frustrating time for him."