Advice on effect of domain redirect and google statistics?

I need someone with exoperience of Google webmaster tools to advise me how to go about stopping adecline in site satistice after introducing a domain redirect. To explain further we have designed a new front page for an existing well rated sit on a variation of the TLD as we needed to use php and not asp for new tools. The website [login to view URL] now redirects to [login to view URL] hence satistics have dropped. Is there a way in Google webmaster tools to resolve this issue and regain our high rating agin? Thanks, UKUAP