Eight months after Target Corporation’s Chief Marketing Officer Michael Francis jumped ship and became president of J.C. Penney Company, the department store retailer said Monday that he’s leaving, effective immediately.

Plano, Texas-based J.C. Penney provided no reason for Francis’ abrupt departure. CEO Ron Johnson said only: “We thank Michael for his hard work at J.C. Penney and wish him the best in his future endeavors.”

Since joining J.C. Penney in October, Francis was responsible for all of the company’s merchandising, marketing, planning and allocation, and product development and sourcing functions.

Johnson, a former Apple executive who became CEO in November, will assume direct responsibility and oversight of the company’s marketing and merchandising functions, J.C. Penney said in its Monday announcement.

After becoming an executive trainee with the Marshall Field’s store in Chicago in 1986, Francis joined Target predecessor Dayton-Hudson Corporation in 1990 when it acquired Marshall Field’s. He held a variety of senior marketing positions in the department store division of Dayton’s and was promoted to executive vice president of Target Corporation in 2001 and to CMO in August 2008.

Before leaving Minneapolis-based Target, Francis was overseeing Target’s first expansion of retail stores beyond U.S. borders. The retailer intends to open 125 to 135 stores in Canada beginning in 2013.

His departure from Target was sudden, and he said in a J.C. Penney-issued news release at the time: “This is a tremendous opportunity for me to get back to department store retail.”

In April, after what it called a “comprehensive search” that included both internal and external candidates, Target hired Jeffrey Jones II—who led a North Carolina-based ad agency—to succeed Francis as its CMO.

Francis’ just-announced departure comes at a time when J.C. Penney is battling a significant drop in customer counts and declining sales. In February, Johnson implemented a new “fair-and-square,” three-tier pricing strategy designed to eliminate the “relentless series of sales, coupons, rebates, and retail gimmicks.” But it has received a cold reception from consumers—who are accustomed to coupons and big markdowns.

J.C. Penney’s same-store sales—sales at stores open at least a year—declined 18.9 percent in the first quarter that ended April 28. Meanwhile, revenue dropped 20 percent to $3.15 billion during the period, and the company reported a $163 million net loss.

“Everything we’ve done hasn’t been perfect. . . . We haven’t communicated our pricing change in a way that customers understand yet,” Johnson reportedly told investors at the Piper Jaffray Consumer Conference earlier this month. “It’s just been kind of confusing.”

According to the Associated Press, Francis infused a “quirky, whimsical style” in J.C. Penney’s recent ads—although critics have argued that it didn’t properly spell out the new pricing strategy.

One TV spot reportedly featured a dog continuously jumping through a hula hoop that a young girl was holding. The text read: “No more jumping through hoops. No coupon clipping. No door busting. Just great prices from the start.” The company also released a monthly magazine that highlighted key items for sale.

J.C. Penney investors didn’t respond favorably to its announcement about Francis’ departure. Shares of the company’s stock closed down 2 percent at $24.33 and fell nearly 6 percent more in after-hours trading on Monday. Shares were trading down 10 percent at $21.85 mid-day Tuesday.