Shares of the company that owns Chili's Grill & Bar and Maggiano's Little Italy restaurants have risen 10 percent to $16.91 since reporting better- than-expected quarterly earnings on Wednesday.

But analysts say Brinker still faces some big challenges.

Sales at stores open at least one year have fallen for the past six consecutive quarters. During the most recent period, same-store sales fell 3.1 percent.

It won’t help that Chili’s, which accounts for about 80 percent of Brinker’s revenue, will end a popular promotion next week. The deal, called “3 for $20,” let consumers share an appetizer, two entrees and a dessert, all for $20. It accounted for about 23 percent of Chili’s sales in the most recent period, says Jeffrey Farmer, an analyst at Jeffries. Once it’s gone, analysts fear customers will flock to the next big chain offering better deals.

And that speaks to Brinker’s core problem: There’s little differentiation between Chili’s and its main competitors such as T. G. I. Friday’s and Applebee’s. Each restaurant offers some of the same menu items –quesadillas, burgers and ribs –in a similar atmosphere.

“Put a blindfold on, and I would be hard pressed to find a customer who could tell a difference,” says Stephen Anderson, analyst with MKM Partners.

That doesn’t bode well for Brinker long-term.

So for stock buyers who want to invest in casual dining, Anderson suggests companies such as Darden (DRI), which operates Red Lobster and Olive Garden, and Buffalo Wild Wings (BWLD).

Those chains haven’t resorted to deep discounts. And unlike Brinker, they operate restaurants that stand out in a crowded industry.