Since its introduction two years ago, the National Basketball Association’s e-sports arm has struggled to draw viewers. Then, with Americans forced to shelter in place in early March, the N.B.A. had a captive audience.

Within days, players for the N.B.A. affiliate, known as the N.B.A. 2K League, were livestreaming games. The league leaned on its counterparts on the courts, setting up online tournaments with W.N.B.A. players. N.B.A. stars even staged their own tournament, which was broadcast on ESPN and drew as many as 387,000 viewers. Sportsbooks took bets on the action.

Even before the pandemic, the N.B.A. showed a penchant for exuberance, announcing team rosters for the e-sports league in a flashy ceremony in New York in February that mimicked the draft for professional sports.

The strategy appears to have helped increase the audience for the N.B.A.’s e-sports venture, in which video game players compete in professional matchups. The N.B.A. 2K League still has only a fraction of the viewers that some other leagues draw, but as it wraps up its third season, which concluded with a championship game on Friday, there are signs of growth.

This season, the audience for games on the Amazon-owned Twitch service increased 76 percent over the year before, to an average of 416,865 unique viewers per game, a spokeswoman for the league said.

“The N.B.A. through 2K has been able to have content flowing through the entirety of coronavirus,” said Rod Breslau, an e-sports consultant known as Slasher.

Created by Take-Two Interactive, the N.B.A. 2K video game series has sold about 94 million copies worldwide. Hoping to capitalize on the success of the series, the N.B.A. started a partnership with Take-Two in 2017 to form the 2K League.

The N.B.A. kept building its e-sports program, saying it generates sponsorship revenue and provides valuable data on viewing habits of cord-cutters. Now, 22 N.B.A. franchises own an e-sports team, with an additional team in Shanghai.

“I think basically it’s a way to try and reach Gen Z consumers,” Jason Chung, executive director of e-sports at the University of New Haven, said of the N.B.A.’s ties to the 2K League. “It’s an avenue they don’t want to miss out on.”

But some cast doubt on the viability of the league when stacked up against more established competitors.

Sports video games generally have a harder time captivating audiences than fantasy games, Mr. Breslau said, adding that the biggest criticism throughout the N.B.A. 2K League’s existence is “No one’s watching.”

The N.B.A. 2K video game series has a big following on YouTube and Twitch, where amateurs stream videos of themselves playing the games. Overall streaming hours for N.B.A. 2K 20, the game around which the league revolves, were 10.1 million in July, according to data from Newzoo, a gaming analytics company.

But streaming hours for professional competition amounted to less than a million in the same month. By comparison, League of Legends, a battle arena game that has been around since 2009, garnered 135.2 million overall streaming hours and 30.2 million e-sports hours in the same month, Newzoo reported.

“The larger 2K community is not totally interested in 2K League,” Mr. Breslau said, noting that other e-sports leagues like the Overwatch League, based around a futuristic shooter game, have similar issues. The game will always have a lot of players, he said, but converting them into e-sports fans is an uphill battle.

E-sports viewership metrics are notoriously fickle, as they lack an industry standard method like Nielsen ratings. That “leaves a lot of wiggle room for reporting figures, especially since these figures are largely proprietary,” said Ryan Rogers, academic coordinator of e-sports programs at Butler University.

Regardless of how many viewers are watching the N.B.A. 2K League, the N.B.A. is notoriously devoted to its business ventures. It waited many years for its developmental league, the G League, and the W.N.B.A. to reach mainstream appeal.

And e-sports remains a potentially lucrative bet. The industry is expected to generate more than $1 billion next year in sponsorships, media rights and merchandise sales, according to Newzoo. Several N.B.A. owners and players invested in other e-sports franchises before and after the introduction of the N.B.A. 2K League.

“I do believe they’re in it for the long haul,” Mr. Chung said. “I think it’s a very smart play.”

Brendan Donohue, the N.B.A. 2K League’s managing director, said he viewed his league as a way to create N.B.A. content.

“On the business side, you’re able to leverage digital content or sponsorship departments to help drive the league,” he said. “It’s speaking to an audience that is becoming harder and harder to reach.”

Attachment to the N.B.A. name has its benefits, too. The N.B.A. players’ 2K tournament in April most likely “opened the eyes” of ESPN executives, Mr. Donohue said. In May, without a lot of other sports to offer, ESPN2 began regularly broadcasting N.B.A. 2K League matches.

The N.B.A. cachet also reels in companies looking to advertise in e-sports. This season, the N.B.A. 2K League added five new partners to its stable of 20, including DoorDash, SAP and Tissot.

“When those brands are trying to figure out ‘How do I invest in e-sports?’ the good thing with us is we’re a trusted brand, and we can hold their hand and help them navigate e-sports,” Mr. Donohue said.

Sponsors can more easily identify with basketball than a world of battle arenas filled with mythical creatures, but traditional sports models don’t always equate to success in e-sports.

To stay competitive, e-sports leagues have mimicked the operations of North American sports leagues, using strategies like standard contracts, trades and tryouts. In February, the N.B.A. 2K League held its annual draft with a lot of sizzle: red carpet, hip-hop performances and cameos by Olympic gold medalists.

E-sports leagues have an obsession with legitimacy, but that’s a mistake, Mr. Rogers said.

“Having big, live events, leagues, jerseys, making them look and feel as much like sports as possible, e-sports is trying to treat itself as equal to” traditional sports, he said. “But that’s not the way the public views it at this point.”

He added that many in the industry did not consider e-sports in that way, either. “They would prefer it treated as distinct,” he said.

The N.B.A. 2K League was set to move to a new Manhattan studio arena, with select games to be played in different cities, but those plans were delayed because of the pandemic. The switch to a remote season allowed the league to “take some chances and try new things,” Mr. Donohue said.

That included special in-season tournaments and a structure that broke away from the regular season/playoff model prevalent in North American sports leagues — a model that allows established leagues to sign lucrative broadcast deals and book arenas.

Mr. Chung compared the inclusion of more tournaments to European soccer, which has the added drama of several opportunities for championships throughout the season, and might be more appealing for an upstart league.

Mr. Donohue said he expected to add more tournaments next season.

“I think they’ve been very clever on the corporate side and the sales side,” Mr. Chung said, “but in terms of promoting the experience and getting the fandom and using influencers to build hype for the game, I think there’s some more work to be done.”