Verdu, who led many of Zynga's studios and creative projects for over three years after a stint at Electronic Arts, announced his exit from the company behind "Farmville" just three weeks after Chief Operating Officer John Schappert resigned.

Morale has suffered as Zynga's share price continued to stumble and revenue growth stalled, sources close to Zynga have said. Zynga closed Tuesday at $3.08, versus its $10 IPO price in December 2011.

But a source familiar with the situation told Reuters that Verdu's departure was motivated primarily by his desire to create a mobile gaming company.

"Being at Zynga in the early days reminded me of how much I love being an entrepreneur. After a lot of soul-searching, I have decided to go back to my roots and start a new company," Verdu said in a blog post.

He thanked Zynga CEO and founder Mark Pincus for his "leadership, friendship, and unwavering support."

In a statement, Pincus said he was proud of Verdu's legacy and would be investing in his new company.

"Zynga will be on the ground floor with Mike on his next venture as an investor in his new start-up," Pincus said.

Zynga shuffled its top management ranks after reporting a net loss in its second quarter. Schappert -- another former Electronic Arts' executive -- left shortly after Zynga said he had ceded many of his game development responsibilities.

Other media reports have said that some other executives have left the company in recent months but Zynga has declined to comment.

The company, one of several highly touted consumer Internet startups in late 2011, blamed its poor quarter on sudden changes to Facebook's algorithm and delays in its pipeline of new titles.

(Reporting by Malathi Nayak; Editing by Edwina Gibbs)

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