McDonald's couldn't compete in the chicken sandwich wars.

On Tuesday, McDonald's announced that US same-store sales grew 4.8% in the most recent quarter, a slowdown from the prior quarter's 5.7% growth. According to executives, the chain faced "competitive pressure" from mid-August through mid-September — a period in which fast-food chains were engaged in the chicken sandwich wars.

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"We said in the US we did gain hamburger share in the quarter," McDonald's chief financial officer Kevin Ozan said on a call with investors. "I think it's fair to assume that … we went a little bit the opposite way on chicken."

Popeyes kicked off a national chicken sandwich war with the launch of its new chicken sandwich in mid-August. Soon after the launch, Popeyes and other chains — including Chick-fil-A, Wendy's, and Church's Chicken — battled on social media about which chicken reigned supreme.

Foot traffic tracker Placer.ai found that customer visits to Popeyes skyrocketed, increasing by more than 100% over the summer baseline average during the peak of the chicken sandwich wars. Other chicken chains also saw a rise in customers, according to Placer.ai, though not as great as Popeyes, which ran out of its chicken sandwiches in just two weeks.

McDonald's has struggled to craft a world-class chicken sandwich as insiders have been buzzing about the need for a new version. Franchisees have pushed the company to make developing a new chicken sandwich a "top priority." And, a sandwich in testing apparently underwhelmed restaurant operators earlier this year, The Wall Street Journal reported.

In early September, the fast-food giant introduced a spicy BBQ chicken sandwich and tenders, an adaptation of the buttermilk chicken that was already on the menu.

The spicy BBQ chicken was not mentioned as a sales driver by McDonald's executives on Tuesday. Instead, executives highlighted fresh beef burgers and the Worldwide Favorites menu, especially the popular Stroopwafel McFlurry.