As part of a major overhaul of its operating structure, Google said on Monday it was creating a new holding company called Alphabet. Google co-founder Larry Page will step down as Google's chief and Pichai was appointed as head of a "slimmed-down" version of the company.

Pichai joined Google just before its 2004 initial public offering and several colleagues who worked with him in the years following said he never seemed anointed for the top job. Instead names that came up as potential future Google chiefs included longtime product executives Salar Kamangar, Marissa Mayer and Susan Wojcicki.

Back then, he was one of a small group of product managers, but his responsibilities escalated from working on new versions of the Google tool bar to overseeing the building of Chrome.

Chrome's rise since its 2008 launch to become the world's dominant browser made Pichai's reputation, and he started overseeing apps like Gmail. He later became head of Android, Google's mobile-phone operating system.

Pichai aided his ascent by never trying to steal the limelight and advancing his agenda through quiet advocacy, according to former colleague Keval Desai.

"He's a very very strong opinionated person who has clear point of views about where product and initiative might go, but he's very good at letting other peoples' opinions emerge before he gives his own," Desai, now an investor, told Reuters.

As time went on, Kamangar was replaced as head of the company's YouTube division last year by Wojcicki. Mayer left in 2012 to run technology company Yahoo (>> Yahoo! Inc.) .

Tony Zingale, the executive chairman of Jive Software, said Pichai was "incredibly insightful and direct", acting as "the quiet yet thoughtful outside director" when he served on the board of the collaboration software maker for several years until July 2013.

Pichai excels at managing relationships, wrote longtime Google product manager Chris Beckmann in a post last year on the question-site Quora.

"Google has politics like any other large company, and Sundar navigated those politics to make his team successful while inflicting the least possible damage on any other team," Beckmann wrote.

Such diplomacy could come in handy as Pichai continues to oversee some big challenges for Google, including navigating an often difficult relationship with partners like South Korea's Samsung Electronics (>> Samsung Electronics Co Ltd), the top Android smartphone maker.

He must also contend with Apple Inc (>> Apple Inc.), which has made bigger inroads with its music services and in wearable devices.

Wall Street appeared to recognize Pichai's talents, with the stock heading up as much as 7 percent in after-hours trading.

"He's a very capable operator, and he has a lot of buy-in from the business side as well as from the engineering side," said Morningstar analyst Rick Summer.

A soccer fan who hails from Tamil Nadu state in southern India, Pichai holds a master's degree from Stanford University and an MBA from the University of Pennsylvania's Wharton School.

(Corrects paragraph 3 spelling to Marissa instead of Merissa, anointed instead of annointed)

(Reporting by Sarah McBride and Julia Love; Editing by Edwina Gibbs)

By Sarah McBride

Stocks treated in this article : Apple Inc., Yahoo! Inc., Google Inc, Samsung Electronics Co Ltd