Wall Street drove the stock of the company down $4.53, or more than 7%, to $57.91 on the announcement.
In a statement, Knight Ridder Chairman-CEO Tony Ridder said he now expects third-quarter earnings to be about 81 cents a share, well below the 87 cents a share that Wall Street analysts had been expecting, according to Thomson Financial/First Call.
Knight Ridder said its August operating revenue fell 1.3% from a year ago to $212 million.
--Matthew Schwartz