An employee arranges Nike basketball shoes on display at the House Of Hoops by Foot Locker retail store at the Beverly Center in Los Angeles.

Shares of Foot Locker spiked 28 percent Friday after the shoe retailer posted stronger-than-expected earnings. If shares close at those levels, it will be the company's single best trading day since 1977.

Foot Locker posted adjusted earnings per share of 87 cents versus an average analyst estimate of 80 cents. The company also beat expectations on revenue, reporting $1.87 billion for the period.

"With the disruption we are witnessing in retail in general and the athletic industry more specifically, we will have to make many critical decisions as we shape our future," said Foot Locker Chairman and CEO Richard Johnson during Friday's earnings call.

"We are making solid progress on several fronts, including three of the biggest initiatives which I have discussed previously: our new digital e-commerce platform, our mobile app platform development, and our new point-of-sale technology," Johnson said. "Each of these multiyear projects will play a key role in enhancing how our customers experience and engage with our banners."

Third-quarter comparable-store sales decreased 3.7 percent.

The shoe store has been in hot water in recent months as Wall Street grows increasingly concerned with retailers. Fears that e-commerce giant Amazon.com may seek to expand into apparel have made it a tough year for Foot Locker shares, now down more than 50 percent since January.

In June, popular shoemaker Nike confirmed plans to sell a limited product assortment on Amazon's U.S. website. Since then, sales of Nike footwear on Amazon have outpaced those at Foot Locker, according to UBS analysis.

Thirteen percent of UBS survey respondents indicated that they prefer to purchase Nike products on Amazon compared with the 9 percent who said they prefer to purchase the same products at Foot Locker.

There have even been reports that the e-commerce behemoth may venture into its own line of athletic apparel. The company is said to be appealing to some of the biggest athletic apparel suppliers for the effort, according to Bloomberg.