New Japan’s growth has been helped by YouTube, which has made New Japan’s matches more accessible to an audience outside of Asia, said Dave Meltzer, publisher of the Wrestling Observer Newsletter, which has followed the sport since 1983. Capitalizing on this rise, New Japan launched an online streaming service — similar to the W.W.E. Network — in December 2014.

“W.W.E. does the ‘entertainment’ part of ‘sports entertainment’ so, so well,” said Cody Rhodes, a New Japan star who left W.W.E. in 2016. “New Japan does the ‘sports’ part of ‘sports entertainment’ like nobody else.”

Last year, New Japan sold out its first two shows in the United States, and all the seats for an event on Sunday in Long Beach, Calif., were gone shortly after going on sale in January.

But evolving from a buzz-worthy niche to mainstream acceptance remains a daunting task.

Professional wrestling has historically been colored by fierce territorial wars, with promoters battling over in-ring talent and the audience that pays to see it. Without serious competition, W.W.E. has built a business that allows its stars to reach levels of opulence never before associated with wrestling, both in income and crossover appeal. A top star like John Cena can appear with W.W.E. one night and guest-host NBC’s “Today” show the next morning. There are, however, only so many Cena-level spots available.

New Japan’s rise has come, in part, from offering its performers more artistic freedom as well as additional avenues for income that are not always available to those working for W.W.E. For example, some wrestlers can negotiate with New Japan to also work for other promotions and to sell their own branded merchandise.

“It’s important to play your music how you want to play it,” Mr. Rhodes said. “To be the writer, director, cameraman, and actor all at once. A company like New Japan builds the set, fills the seats, but allows us to do what we do how we want to do it.”