The Kansas City Chiefs' dramatic overtime victory over the San Francisco 49ers was the most-watched television event in history, according to preliminary television ratings released Monday.

The Chiefs and 49ers reached an estimated 123.4 million average viewers on CBS's broadcast of Super Bowl 58 on Sunday night, with quarterback Patrick Mahomes thowing the game-winning touchdown pass to Mecole Hardman in the final seconds of overtime to give Kansas City its second consecutive Lombardi Trophy and third in the past five years.

Final Nielsen data will be made available Tuesday.

The TV audience, which peaked at the end of the fourth quarter when the Chiefs drove for a game-tying field goal with six seconds remaining to send the game to overtime, broke the previous viewership record set last year. More than 115 million average viewers watched the Chiefs beat the Philadelphia Eagles on Fox, Fox Deportes and streaming services.

Thirteen of the past 15 Super Bowls have now drawn 100 million average viewers or more.

SUPER BOWL CENTRAL: Latest Super Bowl 58 news, stats, odds, matchups and more.

A total of 202.4 million watched all or part of Super Bowl 58 across all platforms, which is also a record that tops last year's Super Bowl of 184 million. The record-setting audience on Paramount+ helped make the game the most-streamed Super Bowl ever.

Sunday's viewership was likely aided by the competitiveness of the game and the presence of several household names, including Mahomes and Chiefs tight end Travis Kelce. The attendance of Kelce's girlfriend, superstar singer Taylor Swift, might have also played a role.

The record-breaking Super Bowl caps a terrific season for the NFL in terms of television ratings. The league averaged 17.9 million viewers per regular-season game, according to Nielsen, and total viewership was up 7% from the previous season.

Contributing: Tom Schad