Zynga CEO Mattrick leaves abruptly, replaced by founder Pincus

"I believe the timing is now right for me to leave as CEO and let Mark lead the company into its next chapter given his passion for the founding vision and his ability to couple our mobile progress with Zynga's unique strengths," Mattrick said in a statement.

Following Mattrick's announcement Wednesday, the company's shares fell more than 9 percent to $2.63. The company's shares have fallen more than 30 percent in the past year.

The company's investors haven't returned to their early enthusiasm that pegged the company's value as high as $20 billion shortly after its initial public offering in 2011.