When Google CEO Sundar Pichai reshuffled his most senior executives earlier this summer, he gave one of the biggest jobs to Prabhakar Raghavan, a former Yahoo research director who had earned acclaim within Google for technology predicting what Gmail users planned to type. Raghavan now heads search and ad products, business lines that together generated $135 billion in revenue last year, or 83% of its total—units Pichai once led. 

Raghavan, 59, will now play a pivotal role in helping Google rebound from what could be its worst year as a public company. He comes to the position after holding various functions at Google, including oversight of the team that launched Zoom competitor Meet, and authoring foundational academic work on web search. He’s expected to move more aggressively than his predecessor to jump-start revenue growth from search engine ads, which fell 10% in the second quarter. Success here is fraught with risks: Antitrust investigators are already scouring for proof that Google leverages its search power to quash competition.