Prior to Walmart, Foran held a number of roles with Woolworths, a leading retailer in Australia and New Zealand. He also "served as the managing director of supermarkets, liquor and petrol with responsibility for more than $40 billion in sales at that time." While running Walmart's Chinese business, the unit made "significant progress" in areas such as merchandise assortment, pricing, store operations and compliance. Foran also made strategic investments in Walmart's supply chain there and improved the store portfolio, according to the release.

"Greg is one of the most talented retailers I've ever met," McMillon said in the release. "His depth of knowledge and global experience will bring a fresh perspective to our business. His passion for fresh food, experience in general merchandise and commitment to e-commerce will help us serve our customers even more effectively for years to come."

"I'm confident that Greg's strong leadership skills and alignment with our culture will serve our customers and associates well," he added.

Walmart spokeswoman Brooke Buchanan told TheStreet in a follow-up interview that Foran's "broad merchandise experience," makes him a "great fit for the position."

"He's passionate about it, loves to walk stores, loves merchandising and has just a really strong background to lead the U.S. business," Buchanan says. The market Foran was in charge of while at Woolworth's is a "competitive mature market, similar to the U.S.," she adds.

Foran will be relocating to Bentonville, Ark., where Walmart is headquartered.

Though some analysts see this as a head-scratcher, not everyone is questioning why Foran was brought in.

"Overall this change is not surprising to us given that the CEO, Doug McMillon, believes a greater emphasis on merchandising is necessary to return the U.S. business to positive comps," JPMorgan Chase analyst Christopher Horvers wrote in a note to clients. "McMillon previously led the international division and is able to implement 'his guy' from that team who is more experienced in merchandising compared to Simon, whose prior experience was COO of WMT and SVP of global business development at Brinker International (EAT)."

As for Simon, speculation has already begun about where he might land next, including whether he would become the next CEO at Target (TGT). However, his non-compete agreement prevents him from taking a job at a Walmart competitor for at least two years, analysts said.

--Written by Laurie Kulikowski in New York.

Disclosure: TheStreet's editorial policy prohibits staff editors, reporters and analysts from holding positions in any individual stocks.

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