BURBANK, Calif. —The Overwatch League christened its inaugural season this month in largely the same ways as any professional sports league’s opening day. The very best players in the world donned uniforms representing their teams. Fans packed an arena, purchasing licensed merchandise in addition to concessions. And announcers broadcast the action for hundreds of thousands more watching at home.

The setting was consistent with a big league pro football, basketball, baseball, soccer or hockey event, but the competition here was a team-based video game, and the new league is the latest development bringing competitive gaming, familiarly known as eSports, closer to the mainstream.

The audience for eSports has surged in recent years and major investors have followed, including owners of traditional sports franchises seeking to reach a young audience traditional sports increasingly miss. Annual revenue has grown more than 40 percent over the past two years and is quickly approaching $1 billion, according to market research firm Newzoo. The International, the major tournament for the game Dota 2, featured a total prize pool of $24 million, with the tournament winners landing $10.8 million. Newzoo projects the total audience for eSports will approach 590 million worldwide by the year 2020.