Supervalu Inc. announced Thursday that a former Wal-Mart executive will become the new CEO of its Save-A-Lot chain, a deep discounter that's vital to the struggling supermarket company's growth plans.

Santiago Roces, most recently senior vice president and general manager of Wal-Mart's small format division, will replace Bill Shaner, a 27-year Supervalu employee who has led St. Louis-based Save-A-Lot since 2006. Shaner "left to pursue other opportunities," Supervalu spokesman Mike Siemienas said.

With several of Eden Prairie-based Supervalu's traditional chains facing falling sales, the company's primary growth vehicle has become Save-A-Lot. The leadership change "suggests that Save-A-Lot's recent performance has failed to live up to management expectations," Credit Suisse analyst Edward Kelly wrote in a research note.

The chain has had relatively disappointing sales vis-à-vis other deep discounters, which have been thriving, Kelly wrote. "We believe [Save-A-Lot's comparable sales to the previous year] were negative through much of 2010."

Supervalu Chief Executive Craig Herkert, who was a high-ranking Wal-Mart executive until taking the reins at Supervalu two years ago, early in his tenure unveiled plans to double Save-A-Lot's size by the end of 2015. It had 1,200 stores at the time and added 92 last year, the most in its history.

Save-A-Lot stores, which don't exist in the Twin Cities, are akin to Aldi supermarkets, in that they operate in a smaller format and primarily sell their own private label brands at deep discounts.

Roces, 48, had been with Wal-Mart since 1998, holding a variety of leadership positions including senior vice president of new business development and customer experience, as well as CEO of Wal-Mart Korea. Santiago's experience at Wal-Mart makes him a "natural fit" for Save-A-Lot, Kelly wrote.

Mike Hughlett • 612-673-7003