A top Internet research analyst believes eSports could be "the next big thing in media and entertainment," and a billion-dollar industry, within just a few years.

Baird Equity Research analyst Colin Sebastian said in an investors note that 2014's $200 million eSports revenue was only the beginning.

Citing revenue streams like tournaments, advertising, broadcasting, and betting, Sebastian expects competitive gaming to break the billion-dollar barrier in 2018, rising to over $1.8 billion by 2020.

eSports has been growing in popularity amongst players and spectators alike, with over 100 million people having viewed tournaments last year.

But publishers and leagues still have a long way to go to break into the mainstream, says Sebastian, as that figure still only represents around 6% of the world's gamers.

Currently, eSports tournaments are frequently held by the games' own publishers, at least in part as promotion for their software.

"As such, eSports is still primarily a marketing, engagement, and retention tool, helping to increase the longevity of games. Beginning next year, we expect this to change."

Sebastian is bullish on the growth of eSports features, saying, "eventually, in our view, most new video games will offer some features of eSports."