Zynga said its CEO, Mark Pincus, is stepping down to be replaced by Don Mattrick, the head of Microsoft's Xbox business.

The maker of "FarmVille" and other games said Monday that Pincus, who founded Zynga in 2007, will stay on as chairman and chief product officer.

Mattrick has served as the president of Microsoft's entertainment business, which includes the Xbox, since 2010. He's been with Microsoft for six years.

Mattrick faces a difficult task. Zynga's stock is down sharply since the company's 2011 initial public offering. Its games have waned in popularity and it announced in June that it was cutting 520 jobs, or about 18 percent of its workforce to save money.

Zynga shares soared nearly 15 percent to $3.19 in after-hours trading.