While doing changes for Panda, I accidentally redirected a page to another URL.The content was served under the new URL for two to three weeks.I noticed this later and then reverted the redirect.The content is now served for the original URL.
This page which was earlier moved by Panda to Page 2 of SERPS is nowhere in the top 10 pages, when I search for it using its primary keyword.I could still find it in page 1 of SERPS (at a lower position than before) using its secondary keyword.This is an extension of the primary keyword.
Example:
Primary keyword - Blue widgets
Secondary keyword - Blue widgets 2010
What could be the reason?