Matthew Boyle

Walmart U.S. CEO Greg Foran, the architect of the revival of Walmart Inc.’s U.S. stores, is departing to run an airline in his native New Zealand, leaving a big hole at the world’s biggest retailer on the cusp of the holiday season.

Walmart Inc., looking to generate more profit from its online unit, wants to start storing and shipping products for third-party vendors for the first time, just as rival Amazon.com Inc. has done for years.

Walmart Inc. has a hole to fill at its online unit, and whoever assumes the role faces a big challenge ahead. The company is searching for a new chief revenue officer for its U.S. e-commerce business, who would work under online leader Marc Lore to help map out its battle plan against Amazon.com, Target Corp. and other rivals.

The impact of Target Corp.’s weekend register glitch won’t show up until the retailer discloses quarterly revenue in August, but it could have cost the company about $50 million in lost sales, according to one analyst.