He told the CET: We talked about defending set pieces better at half time but there is a frailty there.
"We are not big enough, we are not physically strong enough and I have got to question our heart - and I am talking about in the defending third of the pitch. "There are not enough people prepared to spill blood and die for the cause, and I am not just talking about the back four.
"When I came in I said everyone would be given a chance and I think I have done that and been fair to my word. But certainly, the way they are going about it at the moment, I have got to act and I will be looking to strengthen in all areas, if funds are available of course.
"I am sick of talking about battling performances because it is all we ever keep saying. We showed good character but we have frailties that have been exposed, mainly from set pieces."