UPDATED: NBC’s Olympics coverage got a big boost on Sunday night from Jamaican track superstar Usain Bolt, with nearly 35 million viewers tuning in for his 10-seconds of Olympic history.

Bolt’s historic third consecutive gold medal victory in the men’s 100-meter dash and another gold medal from U.S. gymnast phenom Simone Biles lifted NBC’s ratings to a 17.4 household rating and 29 share in Nielsen’s overnight metered markets and a 9.0 rating in adults 18-49. That’s well above the 15.6 household rating that NBC’s primetime coverage of the Rio games has averaged to date.

Viewership peaked from 9:15-9:30 p.m.ET at 34.9 million viewers, or a 21.4/34 household rating, with coverage of the sprinter’s breathtaking and record-setting win with a time of 9.81 seconds.

Biles, meanwhile, earned her third gold of the Rio games for the vault competition. Biles is emerging as one of the U.S. Olympic contingent’s brightest stars as commentators heap praise on the skill of the 19-year-old from Houston.

According to NBC’s total audience delivery measure, 28.1 million viewers watched Olympics coverage across NBCUniversal’s broadcast, cable and digital platforms on Sunday. The vast majority of that audience, 26.7 million viewers, watched NBC’s primetime coverage.

Despite the jolt from bolt, Sunday’s ratings were well below the turnout for the comparable night of the London games in 2012, when it produced a TAD rating of 31.3 million. NBCU has emphasized that much more of the games are available via cable and streaming, and that delayed viewing will be a bigger factor in the 2016 games.

The top local markets for Sunday’s coverage were: Salt Lake City (20.5/40), Austin, Texas (20.2/35), Columbus, Ohio (19.9/33), Richmond, Va. (19.9/32), and Denver (19.7/38).

Standout Athletes of the 2016 Rio Olympics