Fulham manager Roy Hodgson fears Chris Foy's refereeing decisions may go in Birmingham's favour when the two sides meet at St Andrews on Saturday.
Alex McLeish's side were denied their second away win of the season two weeks ago thanks to Steven Gerrard's controversial second-half penalty.
Hodgson admits that decision could play into Blues' hands when Foy takes charge of Saturday's match. He said: "One is always worried that any compensation that is due them will come at your expense so we'll have to tread very carefully there."
McLeish was left furious with the penalty decision, which was awarded by Peter Walton when David Ngog fell in the box although replays showed the Frenchman made no contact with Toffees midfielder Lee Carsley.
Hodgson added: "If we are talking on the sympathy front then Birmingham will be right up there in the forefront at the moment because obviously the people at Birmingham thought they were harshly done by with the refereeing decisions so that's not good for us.
"I don't think any referee sets out deliberately to do that but certainly people will feel a lot of sympathy with Birmingham after their great performance at Liverpool."
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