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What: Shares of restaurant operator Ruby Tuesday (NYSE:RT) plummeted 18% this morning after its quarterly results and outlook disappointed Wall Street.

So what: The shares have plunged over the past year on slumping sales, and today's first-quarter results -- a loss of $0.36 per share on revenue of $289.7 million -- coupled with downbeat guidance for the second quarter suggest that things aren't picking up anytime soon. While management said that initiatives to re-establish the Ruby Tuesday brand are gaining traction, the same-store sales decline of 11% suggests the competitive environment might be too intense to overcome. 

Now what: Ruby Tuesday now expects second-quarter same-store sales to drop in the high single digits, with sequential improvement as the year progresses. "I remain confident in our brand transformation strategy and in our team's ability to successfully execute our plans," said CEO J.J. Buettgen. "Looking ahead to the remainder of fiscal 2014, our top priorities are driving increased guest counts and profitable sales growth." Given Ruby Tuesday's clearly weakening competitive position, however, I wouldn't be so quick to buy that turnaround talk. 

Fool contributor Brian Pacampara has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.