Megson said: "Johan is part of the squad but he needs to accept like everyone else that he has got to deliver.
"It doesn't matter to me how much he cost, where he came from, reputation. He has to deliver. He has got to start doing more. He has got a great touch, great awareness but he has got to start doing a lot more for us.
"We know what we are getting with Kevin Davies. We know his quality in the air, the size, power and pace of him and, most of all, the work-rate that Kevin puts in.
"It doesn't matter to me whether Johan is an international player from Sweden, or whether they have cost a lot of money, or whether they are young players who have cost nothing."