Scott Carson admits West Brom's inability to field a settled back four has been a key factor in their poor form this season.
The unavailability of defenders Abdoulaye Meite, Jonas Olsson, Leon Barnett, Ryan Donk, Neil Clement and Gianni Zuiverloon for lengthy spells through injury has not helped the Baggies, who looked destined to make an immediate return to the Coca-Cola Championship.
Goalkeeper Carson said: "The biggest problem here this season, because of injuries and things, is we've never managed to put out the same defence week after week for any real period of time."
He added: "When you have the same back four every week, it gets a bit easier. You know what is going to happen. When it changes every game, with injuries and things like that, it isn't easy - and hasn't been easy for the manager.
"You are always making changes and adjusting because one defender plays in one way while another has different strengths so you are always compensating for things.
"You can't expect to click straight away, to get into the same way of thinking with people. It takes time to get an understanding and injuries mean we have had a lot of changes."
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