Roberto Di Matteo admits his West Brom side need to tighten up at the back after the 3-2 win over Preston.
Albion have conceded 42 goals so far this season after Sean St Ledger and Neil Mellor struck for Preston to leave the result in some doubt.
"I am disappointed with the two goals we conceded as they are mistakes we shouldn't be making," said Di Matteo.
"Defensively we need to do better, there is no question about that.
"But on the other hand we have had to change the back four quite often and that doesn't help. It is about finding a balance where you are solid but you don't lose too much going forward.
"I would like to keep more clean sheets and be more solid."
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