SEOUL, March 9 -- AlphaGo, the computer created by DeepMind, the Artificial Intelligence (AI) arm of Google, beats Go-chess grandmaster Lee Sedol of South Korea in the opening match of human vs. machine showdown, leading 1-0 in the best-of-five series on Wednesday.

After about three and a half hours of play, Lee, one of the greatest players of the ancient board game who has topped the world ranking for most of the past decade, resigned when it became clear the AlphaGo had taken an unassailable lead.

The result is out of the anticipation of many experts. It's expected that Lee will be the winner in the 3,000-year-old Chinese game for many, including Kai-Fu Lee, the former Google vice president, who believed AlphaGo's chance to win is slim.

Playing black in Game One, Lee made the first move of the match being held on the sixth floor of the Four Seasons hotel in Seoul.

The match-up has sparked enough interest to warrant an Internet live-stream as well as live TV broadcasts in South Korea, China and Japan.

The five-game battle for supremacy between human and machine is being seen as a major test of what scientists and engineers have achieved in the sphere of AI over the past 10 years or so.

The most famous AI victory to date came in 1997, when the IBM-developed supercomputer Deep Blue beat the then-world class chess champion Garry Kasparov.

AlphaGo drew the world attention when it crushed European champion Fan Hui in a 5-0 whitewash in January -- the first time a computer program has beaten a professional player of the game, sending shockwaves through the Go community

Played on a board with a 19x19 grid of black lines, Go is such a complex game that enthusiasts hoped it would be years, or perhaps decades, before machines would be able to triumph over the best human players, but now it's evident that AI technology is much advanced than many have assumed.

Lee confessed to some pre-match nerves at a press conference on Tuesday, avoiding to take a high profile stance. "Now I think I may not beat AlphaGo by such a large margin like 5-0. It's only right that I'm a little nervous about the match," Lee said Tuesday.

The winner of the match-up will get a prize of one million dollars. Game Two will be played on Thursday.