After leaving only four months ago to work for eBay Inc., marketing executive Carter Cast is rejoining Walmart.com as the company"s new president.

In an announcement Thursday, Wal-Mart Stores Inc. said Cast, 41, who was formerly Walmart.com"s senior vice president of merchandising and marketing, will return to the company on July 5 as president of the Brisbane, Calif-based online merchant.

As president, Cast will oversee all day-to-day operations at Walmart.com and focus on expanding the site"s featured merchandise and services, the company said.

Cast left Walmart.com four months ago to become eBay"s chief marketing officer.

He will take over the president"s post at Walmart.com from John Fleming, who in April was promoted to executive vice president and chief marketing officer at Wal-Mart.

"We"re extremely pleased to have Carter lead our fast-growing online business," Fleming said in a statement. "Carter is an outstanding e-commerce and management talent who will help us further leverage the Wal-Mart brand and deepen our online commitment to customers."

Cast joined Walmart.com in 2000 as vice president of marketing and was then promoted in 2002 to senior vice president of merchandising and marketing.

"I"m very proud to have been part of the eBay culture and to have worked with a committed, talented group of people," Cast said in a statement. "However, the opportunity to return as the new president of Walmart.com -- the company I had a hand in building -- was one I couldn"t refuse. I"m very excited to rejoin Walmart.com in this new role."

Hani Durzy, a spokesman for San Jose-based eBay, said the online auction company is "disappointed" that Cast has departed but that eBay wishes him luck in his new role.