Seoul, March 9

Google’s AlphaGo computer programme today won the first of five matches against one of the world’s top players of a complex board game, Go, marking a dramatic advance for the field of artificial intelligence (AI).

South Korean professional player Lee Sedol, the holder of 18 international titles, conceded defeat in a match broadcast live, with one YouTube stream drawing tens of thousands of spectators worldwide, while domestic television gave frequent updates.

“We landed on the moon,” Demis Hassabis, chief executive and co-founder of Google subsidiary DeepMind, which built AlphaGo, said in a tweet after the victory. “So proud of the team!”

AlphaGo had made history in October, by becoming the first computer programme ever to beat a human professional player at the ancient Asian game, which many experts consider to be the most fiendishly complicated of its kind.

But 33-year-old Lee, a much more challenging opponent, was considered a bigger hurdle for a machine to vanquish.

Lee expressed surprise at his loss. “I didn’t think AlphaGo would play the game in such a perfect manner,” he said. “I’d like to express my respect to programmers for making such an amazing programme.”

Go, most popular in countries such as China, South Korea and Japan, involves two contestants moving black and white stones on a square grid, with the aim of seizing the most territory.

Experts did not expect an AI programme to beat a human professional for at least a decade, until AlphaGo’s victory last year over player Fan Hui.