(Bloomberg) -- Google’s top search executive said concerns about Amazon.com Inc. keep him awake at night as the company loses users to the online retail giant and newer apps such as ByteDance Ltd.’s TikTok.

Testifying as part of the Justice Department’s antitrust case against Google Thursday, Prabhakar Raghavan, a Google senior vice president, said young people in particular are using apps such as TikTok and Meta Platforms Inc.’s Instagram and WhatsApp, where they spend an average of four hours per day.

“I feel a keen sense not to become the next roadkill,” said Raghavan, one of the first employees the Alphabet Inc. unit has called in its defense. For young people, “Grandpa Google knows the answer and will help you with homework. But when it comes to doing interesting things, they like to start elsewhere.”

The Justice Department rested its case last week, arguing that Google illegally maintains a monopoly in online search by paying more than $10 billion a year to tech rivals, smartphone makers and wireless providers in exchange for being set as the preselected “default” on mobile phones and web browsers. Google, in part through Raghavan’s testimony, argues that the company faces staunch competition from not only other search engines but other online sites that young people engage with for everything from entertainment to shopping to cooking.

Raghavan’s testimony served as a rebuttal to the idea that Google could be a “one-stop shop” for internet search, an argument made earlier in the trial by Justice Department witnesses, including Microsoft Corp. Chief Executive Officer Satya Nadella. US v. Google, which is expected to last 10 weeks, is the government’s biggest tech monopoly trial of the last two decades.

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Raghavan underscored that Google was at risk of losing market share to apps like TikTok and Instagram, particularly because engaging with them diverges so sharply from traditional online search behavior — going to a search engine via a web browser, and typing a query. 

“The fastest growing section of queries is young people using their camera to point to things,” Raghavan said on the witness stand.

“Our user research shows where young people go, older users follow,” he added, explaining why Google has focused on TikTok. Raghavan made similar remarks in 2022, relying on internal Google research, stating that “something like almost 40% of young people, when they’re looking for a place for lunch, they don’t go to Google Maps or Search. They go to TikTok or Instagram.”

Pandu Nayak, a Google vice president for search, testified last week that Google has focused on TikTok of late to figure out how younger people are searching for information.

“Young people particularly are increasingly turning to TikTok for their information needs, and we want to understand what is it that they’re doing there, what are they finding useful, what should we do with Google to address that,” he said.

Amazon, the e-commerce giant, is also encroaching on Google’s search dominance.

“Users are increasingly beginning their shopping journeys on Amazon,” said Raghavan, echoing testimony from an earlier Google executive who said that advertisers have been moving from the search engine to the retail giant.

A 2018 Google presentation displayed in court Thursday referred to overlapping products it had with the online retailer and listed risks to its business in four areas: retail, queries, ads and cloud computing. 

“They are doing a great job of using their closed loop to attract ad dollars in a way we cannot because we do not have a closed loop,” Raghavan said.

On cross-examination, a Justice Department lawyer sought to show that there was no evidence that a person shopping more on Amazon meant that they were searching less on Google. He cited Google’s own internal research effort in 2019, called Project Charlotte, that came to that conclusion. 

“People who end up spending more time on Amazon might also be the same kinds of people who spend more time on Google,” Raghavan testified under questioning from the DOJ lawyer, Joshua Hafenbrack. “One does not cause the other.”

Later, Hafenbrack asked how much Amazon pays Google for prominent advertising visibility on the search service. 

“Billions of dollars,” Raghavan said. 

(Updates with additional testimony)

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