Olympic sponsors shelling out $3.3 billion to participate in the Tokyo Games have had to contend with the uncertainty around COVID-19, lack of in-person spectators, lagging TV viewership and absence of some high-profile athletes. But one bright spot in an otherwise chaotic Summer Games has been ByteDance’s short-form video app TikTok, which has become the app du jour to reach Gen Zers.

Read: Everything you need to know about TikTok advertising.

Comcast, parent of NBCUniversal, which is broadcasting the Games, has leaned into the app to compile user-generated content to create an entire 30-second commercial set to run during the closing ceremony on Sunday. The brand is gathering the content through a hashtag challenge around #XfinityFanthem, and has onboarded a number of Olympians, professional gamers and creators to participate. The finished commercial will be part of its Xfinity Olympics campaign, which puts a spin on the Olympic Games’ theme song “Bugler’s Dream.”

With only a few days left until the Olympics wraps, videos that carry the hashtag have generated 6 billion views. Considering that viewership of the games across linear and streaming NBCU properties has been averaging roughly 16.8 million viewers, down about 36% from the 2016 Rio Games, it's easy to see why brands are seeing finding their own gold with TikTok.

“TikTok is a great platform for brand storytelling and given its relevance right now and our specific focus on music, it felt especially right for us in this moment,” says Carlo Cavallone, global co-chief creative officer and partner at 72andSunny, the agency behind Comcast's campaign.

Even Olympic sponsors without dedicated TikTok strategies like Samsung, Coca-Cola, Ralph Lauren and Asics are getting more exposure from the platform thanks to relaxed restrictions from the Olympic Committee this year, allowing Olympians to cut their own deals with sponsors, posting on their behalf and sharing their experience. Outside of athlete postings, the Olympics enforce strict intellectual property laws for non-sponsors, prohibiting them from using any Olympics branding in content, even related imagery.

Many of the 600 USA Olympians—such as rugby stars Ilona Maher and Cody Melphy and shot put star Raven Saunders—have become popular TikTok celebrities by sharing their experience during their stay at the Olympic Village, moments viewers could not experience through broadcast or streaming. These athletes have shared posts about everything from how their laundry gets washed to their cardboard beds, which have gone viral on the platform due to assumptions that they are made to prevent Olympians from having sex. 

Olympians with major brand sponsorships have featured prominantly on TikTok showing off the swag they've received, with these videos getting millions of views. Even brands that weren’t official “ring bearers” like Skims, Nike and Oakley benefited from sending free items to Olympians to share with their TikTok followers.

“This year is unique as in-person fans have been restricted from the Games and the International Olympic Committee has lifted restrictions on posting which provides viewers and fans an inside look into how the athletes are interacting before and after their events,” says Mary Keane-Dawson, CEO of influencer agency Takumi. “Brands had a huge opportunity because of the lifted restrictions to ensure they are providing fodder for athletes to interact with.”

In a video that has been seen 13.2 million times, Melphy shows off gear from Samsung, Ralph Lauren, Nike and Oakley. In another video, he introduces followers to Coca-Cola’s free vending machine at the village.

Maher, meanwhile, has been showing off her free Ralph Lauren clothing in videos in which she comments about Olympian life.

For Skims, the official underwear, loungewear and pajamas provider for female athletes at the Games, TikTok proved to be a nice boost after the brand had to cancel multiple activations on the ground in Tokyo when spectators were prohibited from being in the stands. The Kim Kardashian-founded brand gifted items to Olympians that are being made available to the public. One video posted by American pole vaulter Katie Nageotte, for instance, has been viewed over 4.5 million times.

“Now, there are a lot more ways to engage rather than hoping your right customer is tuning in at the right time,” says Ali Fazal, VP of marketing at influencer platform Grin, which connected Skims with athletes like Nageotte. “It’s not that Olympians are necessarily the most popular or most followed creators, but Skims is focusing on making their brand a part of a broader narrative that has really nostalgic connotative value.”

Elizabeth Koenig, social media strategist at social media agency The Social Element, believes the success brands have seen from this Olympics on channels like TikTok will extend to future Games. “What may be interesting in future Olympics are brand partnerships with athletes who will guarantee to be active on TikTok or other channels,” she says.

Still, Koenig points out that there is risk in any partnership. For this Olympics, the agency worked with Oreo around the brand’s partnership with Simone Biles. When Biles backed out of the competition due to her mental health, the brand saw hateful comments across its social channels. The agency was able to quickly scrub the remarks, but the brand still had to deal with those awkward moments, says Koenig.

Not just TikTok 

If TikTok takes the gold, YouTube has earned the silver. While most Olympic sponsors are seeing views of their ads only reach thousands or tens of thousands views on the platform, several brands are cracking a million. P&G’s “Lead With Love” Olympics commercial, honoring moms who have raised good humans as well as top athletes, has garnered nearly 3 million views, while the commercial for Milk Processor Education Program, or MilkPep, where Olympians like cyclist Kristin Armstrong and karate champion Ariel Torres train behind the fridge in a grocery store, has seen about 1.2 million views on the platform. Omega stands as an outlier: the watch brand’s Olympic commercial has been viewed more than 55 million times, generating 1,000 comments and 25,000 likes.

Olympic sponsors are eager to find eyeballs wherever they can get them, as viewership of the Summer Games on TV has been lackluster. The total audience across linear and streaming for the first night of competition was 15.9 million viewers, down 32% from the same night from the Rio Olympics, according to Nielsen data. Since then, viewership has fluctuated, but continue to trail behind the 2016 Rio Games. One of the largest dips was on the Friday of the first week of competition when linear viewers dipped to 10.5 million viewers, a 56% drop compared to the same night during the Rio Olympics, according to Nielsen.

The Olympics continues a trend in marquee events experiencing ratings erosion. The Super Bowl this year posted its lowest viewership in 14 years, while the Oscars recorded its worst TV ratings in its 68-year history.

Certainly TikTok posts tied to the Olympics have helped the platform in its efforts to become the social media platform of the moment. The app is seeing its growth outpace competitors during the Olympics, although it still lags behind heavyweights like YouTube and Instagram in terms of active users. On Android, daily active TikTok users peaked to 27.6 million between July 23 and August 2, a 4% increase from the 26.4 million the app saw in the 11-day time period leading up to the Games, according to analytics company Similarweb. That percentage is four times the growth Instagram and YouTube have seen in the same period. YouTube saw a 1.7% bump to 62.4 million daily active Android users, while Instagram saw a 1.2% jump to 33.6 million.