Target Corp. Chief Executive Brian Cornell took another big step in reshaping the company Monday by elevating Chief Financial Officer John Mulligan to a new role and reaching outside the company for his successor.

Mulligan, a longtime Target executive who has been CFO since 2012 and was acting chief executive last year, was promoted to the new position of executive vice president and chief operating officer.

Cornell hired Cathy Smith, a former executive for Express Scripts and Wal-Mart, as Target's chief financial officer, starting Sept. 1.

Smith, 51, is the latest top-level executive Cornell has brought in from outside the company since he became chief executive a year ago.

"As our new CFO, Cathy brings significant business and retail expertise to Target," Cornell said in a statement. "Her background will be integral to accelerating our long-term growth strategy."

Cornell is himself the first chief executive at Target to come from outside the company. Since arriving last August, he has tapped Mike McNamara, a former Tesco executive, to be Target's chief information officer. He also has brought in Anne Dament from Safeway to be a senior vice president of grocery. Jackie Hourigan Rice, Target's chief risk and compliance officer and a former General Motors executive, was also hired last year during Cornell's watch.

The newly-created COO job reflects Cornell's eagerness to improve Target's operations. He told suppliers last week at an annual vendors summit that the retailer needs a lot of improvement in keeping shelves better stocked.

In the COO role, Mulligan will be in charge of stores and the logistics of supplying them, something that was previously one of the responsibilities of Kathee Tesija, the chief merchandising officer who is leaving the company. Target is in the midst of a comprehensive search to fill her position, which is crucial to the retailer, which prides itself on its cheap-chic reputation.

Target spokeswoman Katie Boylan noted that by splitting these two executive positions, Target is separating its merchants from its planners. "That's meant to build deeper expertise and to allow them to clearly focus and to have greater accountability," Boylan said.

Mulligan led the company during the tricky transition after the Target board in May 2014 ousted former Chief Executive Gregg Steinhafel.

"John has unparalleled expertise in Target's business and I am very pleased that he will be assuming this new leadership position," Cornell said in the statement. "Bringing together key operations functions under John will put Target on a more progressive path to transformation and help us break down barriers to deliver improvements across our business."

Both Smith and Mulligan will take part in the conference call Target will host with investors on Wednesday when it reports second quarter results.

Smith will be paid a base salary of $725,000 and be eligible for a bonus of up to 80 percent of that amount. She'll also receive a signing bonus of $500,000 and stock awards worth more than $2 million.

While Cornell also worked for Wal-Mart, in its Sam's Club unit, he did not work directly with Smith, who was in the company's international division.

Last week, Target announced that it added two new board directors. Donald Knauss, former chief executive of the Clorox Co., and Robert Edwards, former CEO of Safeway, joined the board.