Zynga, the social games maker that has stumbled badly over the last year, said it had replaced its founder and chief executive, Mark Pincus, with the head of Microsoft’s Xbox video game business, Don Mattrick.
The change, announced Monday afternoon, came after a series of miscalculations and poor management decisions by Mr. Pincus threatened to transform Zynga from one of the hottest game start-ups ever into one of its most spectacular flameouts. After Mr. Pincus figured out before anyone else how games like FarmVille could get friends playing against one another on Facebook, he seemed unable to repeat the formula on today’s popular game devices, smartphones and tablets.
Zynga’s stock is down nearly 70 percent since it sold shares to the public in late 2011. Last month it laid off nearly a fifth of its work force.
In hiring Mr. Mattrick, Zynga is following a familiar rite of passage at young technology companies, which often look to seasoned managers to aid their transition from start-ups run by creative, headstrong founders into bigger enterprises. Google, for instance, brought in Eric Schmidt as chief executive to help manage the company with its co-founders Larry Page and Sergey Brin.
Some founders of troubled Internet companies have not been able to hang on, including Andrew Mason, the former chief executive of Groupon, who was fired from the coupon service in February after his missteps put him on the wrong side of its board of directors.
Mr. Pincus, who will remain at Zynga as chairman and chief product officer, worked hard on Monday to portray himself as a strong supporter of hiring Mr. Mattrick. In a message to Zynga employees, Mr. Pincus said he had long told Zynga’s board, including Bing Gordon, a stalwart of the games business and friend of Mr. Mattrick’s, that “if I could find someone who could do a better job as our C.E.O. I’d do all I could to recruit and bring that person in.”
“I’m confident that Don is that leader,” Mr. Pincus wrote. For good measure, Mr. Pincus concluded a Twitter post on Mr. Mattrick’s hiring with the hashtag: #internettreasure.
In Mr. Mattrick, Zynga has found a rare combination of impeccable creative credentials in the games business and strong business acumen. A programmer from Vancouver, British Columbia, who dropped out of college to create games, Mr. Mattrick founded a games start-up at the age of 17. He sold the start-up for $11 million to Electronic Arts in 1991, where it became a factory for some of EA’s biggest games hits, including the car racing game Need for Speed.
He is a hard-core gamer himself, though a busy one. He once confirmed to a reporter that he hired a college student to play the online fantasy game World of Warcraft using Mr. Mattrick’s account so he could more swiftly improve the powers of his game character.
After 14 years at EA, Mr. Mattrick joined Microsoft in 2007 and helped that company expand the audience for its Xbox 360 game console. He oversaw the introduction of its Kinect motion-sensor, which made the game system more accessible to casual gamers.
Mr. Mattrick does not, however, have a strong background in mobile games, where Zynga needs the most help. There are plenty of megahits in mobile games, from Angry Birds to the addictive puzzle game currently at the top of download charts, Candy Crush. But that formula for mobile success has largely eluded Zynga and it isn’t readily clear Mr. Mattrick has the background to help the company solve that problem.
“I think the solution is mobile so I’m not sure Don is the guy,” said Michael Pachter, an analyst at Wedbush Securities. “You need a hit. It’s fluky stuff.”
Zynga has also been hit with a string of departures by executives who, like Mr. Mattrick, used to work at Electronic Arts. The most prominent was John Schappert, Zynga’s former chief operating officer.
The timing of Mr. Mattrick’s departure was particularly bad for Microsoft, which plans to release a new game console, the Xbox One, in time for the holiday shopping season. Mr. Mattrick, the president of Microsoft’s interactive entertainment business, has had a rocky few weeks since the unusual public outcry that followed the revelation last month of many important details about Xbox One at the E3 game conference.
Gamers denounced Microsoft’s plan to let game publishers prevent the resale of Xbox One game discs in used-game stores, forcing the company to reverse its policy. Although the controversy looked like a setback for Mr. Mattrick, his departure did not appear to be directly related to it, according to one person.
All Things Digital first reported news of Mr. Mattrick’s hiring by Zynga.
Mr. Mattrick, 49, was also talking to Electronic Arts about becoming chief executive of that company, said people briefed on the discussion who declined to be named because the discussions were private. While Zynga is struggling to find mobile hits, there is little danger of it going out of business in the near term. The company has a sizable store of cash from its initial public offering, with more than $1 billion in cash and marketable securities.
It remains to be seen whether Mr. Pincus, who still holds 61 percent of the voting power in the company through his Zynga shares, will give Mr. Mattrick the freedom to run the company the way he wants. Zynga said that Mr. Mattrick will join Mr. Pincus on a newly formed executive committee to manage the company’s affairs between board meetings.
One person close to Zynga who declined to be named said that Mr. Pincus was serious about letting Mr. Mattrick run the company and that Mr. Mattrick would not have accepted the job if he thought Mr. Pincus was likely to meddle.
John Doerr, the venture capitalist and Zynga board member, said in a statement that the change would allow Mr. Pincus to focus more on products. “This also is a win for Mark, who can devote his full attention to conceiving and building the best social games in the world,” Mr. Doerr said.
An earlier version of this post stated incorrectly Mr. Mattrick's age when he sold his company. He was 17 when he founded the company, not when he sold it in 1991.