Just three months after ex-Google executive Marissa Mayer became CEO, web firm Yahoo has poached another former Google employee to become its chief operating officer (COO).

Henrique de Castro has been serving as vice president of Google’s worldwide partner business solutions group, where he was responsible for advertising platforms and services for Google’s publisher and commerce partners.

He will now be responsible for managing Yahoo’s sales, operations, media and business development worldwide, reporting directly to Mayer.

“I’m personally excited to have him join Yahoo’s strong leadership team,” said Mayer.

De Castro has also led Google’s media, mobile and platforms organisation, and spent two years at Dell, managing sales and business development across Western Europe. He will join the company on January 22, 2013, unless Google agrees to let him leave prior to that date.

“This is a pivotal point in Yahoo!’s history, and I believe strongly in the opportunity ahead,” said de Castro.  “I can’t wait to join Marissa and the team and get started.”