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Susan Wojcicki, SVP of advertising for Google, will lead its YouTube unit, sources said.

The news was first reported as likely by The Information late Tuesday night.

Wojcicki was employee No. 16 at Google, and she famously housed the company in the early days out of her Menlo Park, Calif., garage.

Salar Kamangar, who was Google’s ninth employee and had led YouTube since co-founder Chad Hurley departed in 2010, is expected to shift to another role within Google.

Kamangar’s top two lieutenants were Shishir Mehrotra and Robert Kyncl, who were both recently given promotions in their capacities as tech and business leaders, respectively.

Kamangar’s departure from the top spot at YouTube had been rumored for at least a year, with many assuming that Mehrotra would be his replacement.

The move solves a management problem at Google, as Wojcicki had recently had her responsibilities split with Sridhar Ramaswamy being added to Google’s senior team to direct commerce initiatives.

Wojcicki had been interested in running her own thing, sources said, and she had also been a recruitment target for a venture capital or perhaps a CEO role. The last big management change Page made was last spring, when he put Chrome boss Sundar Pichai in charge of Google’s Android mobile unit, which had been run by Andy Rubin. Page also shuffled his team around after taking over Google in the spring of 2011. (Update: An earlier version of this story incorrectly reported that Page had not made major management changes since 2011.) Sources said more changes are expected in the coming days.

It’s unclear what Wojcicki’s move will mean for YouTube itself. Over the past few years the video site has generated grumbling from some programmers, who have found it hard to make significant money there, and from some advertisers, who would like it to behave more like a TV network. But there has never been any sign that either Kamangar or Page thought YouTube needed a significant overhaul.

Google has never broken out YouTube’s financials, and estimates vary widely, but for what it’s worth, eMarketer thinks the site generated $5.6 billion in ad revenue last year. It attracts more than a billion visitors a month, with more than 40 percent of them coming via their phones and tablets.

And while people outside of YouTube have pined for a leader who was comfortable schmoozing with advertisers and Hollywood, Wojcicki isn’t that type of person. She has kept a rather low profile, despite her long history at the company and impact as a leader.

She does like YouTube, though: In a speech at Google’s developer conference last year, Wojcicki said she had been a strong proponent of Google’s decision to buy YouTube for $1.65 billion in 2006, after seeing a user-uploaded video of kids lip-syncing to the Backstreet Boys get far more traffic on Google Video than the premium studio content for which she had helped cut deals.

And late last year, in one of her rare tweets, she highlighted some of the site’s ads:

https://twitter.com/SusanWojcicki/status/413075014145949697