• MLB viewership numbers on TNT Sports and Fox Sports have been strong throughout the playoffs.
• Star power and compelling storylines have helped draw attention.
• The solid postseason is a continuation of a 2024 regular season when fan attendance and engagement increased.

Major League Baseball's postseason has been knocking it out of the park.

The National League Championship Series' first game between the New York Mets and Los Angeles Dodgers on Sunday averaged 8.26 million viewers across Fox Sports' TV networks and streaming, making it the most-watched LCS game on any network since 2009, according to Fox Sports.

The first game of the American League Championship Series on Monday night between the New York Yankees and Cleveland Guardians saw an uptick of 4% from 2023, grossing 3.9 million viewers, according to a TNT Sports spokesperson.

Both series were competing for national attention during "Sunday Night Football" and "Monday Night Football," where all three of New York's National Football League teams were playing in the primetime slots.

The championship series gains come right after four successful league division series for MLB and its broadcast partners. The American League Division Series averaged three million viewers, a more than 20% increase from 2023, according to TNT Sports. Viewership for the National League Division Series rose, too, with game four in each series climbing from 2022.

Concerns have grown in recent years that MLB's cultural relevance is falling, namely as younger generations perceived to have shorter attention spans age into key demographics for media companies. Highlights and clips have become go-to programming for sports broadcasters.

Last year's World Series between the Texas Rangers and Arizona Diamondbacks also tracked the worst TV ratings in the championship series' history, although some reportedly had attributed it to the fact that the teams did not have much national appeal.

The 2024 regular season was a success for MLB, as well. The league said it recorded increases in attendance, fan engagement, streaming and viewership, something it attributes to the shorter games —helped by a pitch clock introduced last season — and rule changes that have created more in-game action.

"The increased enthusiasm baseball fans of all ages have shown the last two seasons is evident in all of the ways we track fan engagement," MLB Commissioner Rob Manfred said in a release. "Building off last year's momentum, the 2024 season was memorable with historic performances, emerging young stars, a series of successful special events, and tight pennant races."

MLB has recently implemented several rule changes designed to increase action in games such as making the bases larger and restricting the shift. The league has also leaned in to its generational stars such as Shohei Ohtani and Aaron Judge, who are on the Dodgers and Yankees, respectively, and would face off in the World Series if each of their teams win their LCS.

"The two most storied franchises in Major League Baseball coming together and playing in the World Series, there couldn't be anything better for baseball," Eldridge Industries CEO Todd Boehly said Tuesday to CNBC's Scott Wapner on "Halftime Report." Boehly's firm is an owner of the Dodgers, among other professional teams.

The two other remaining teams, the Mets and Guardians, have their own draws. The Mets turned around their season in June after a winning streak, which followed a McDonald's mascot, Grimace, throwing out a first pitch at a game.

The Guardians righted their season after giving up their division lead to the Kansas City Royals at the end of August behind a hot September from their star Jose Ramirez.

The Yankees have a 2-0 game lead against the Guardians, and the Mets-Dodgers series is tied at 1-1.