Standard & Poor's Ratings Services on Friday downgraded its outlook on Sears Holdings Corp., which operates Sears and Kmart stores and clothing seller Lands End, to negative from stable.

S&P said it expects weak consumer demand and intense competition to hurt the company.

The ratings agency also affirmed all its ratings on the Hoffman Estates, Ill.-based company, including its "BB-negative" corporate credit rating.

"The ratings on Sears reflect our expectations that sales will remain under pressure because of intense competition and weak consumer demand in the fragile economic recovery for high-ticket items such as appliances," said S&P credit analyst Ana Lai.

S&P said it is concerned that the negative sales trends could continue in the fourth quarter, resulting in weaker-than-expected operating results amid intense competition, weak consumer spending for home appliances and subpar store execution.

The outlook downgrade comes a day after the company reported that its third-quarter loss nearly doubled, dragged down by weak sales of appliances and clothing at its Sears chain.

Shares of Sears fell 32 cents to $63.57 in aftermarket trading on Friday. The stock added 5 cents to $63.75 during the regular session.