A Google software programme has drawn first blood in the latest contest between man and machine, winning the first of five planned games against a South Korean champion in the boardgame Go.
The AlphaGo programme bested Lee Sedol in a little more than two hours on Wednesday.
The software adopted strategies of reinforcing its own groups of pieces while probing its opponent for weaknesses, "the same as a really good Go player," match commentator Michael Redmond was quoted as saying by Wired online.
On Tuesday after a meeting with the AlphaGo programme team, Lee admitted: "If I make mistakes, I could lose."
The 33-year-old professional Go player is playing for prize money of 1 million dollars. Before the first match, bookmakers were offering odds of around even for the two opponents.
The rules of Go, which originates in China, are easy in principle: two players try to conquer spaces with white and black stones on the board, which is divided by vertical and horizontal lines into a grid.
AlphaGo was developed by Google's DeepMind AI branch to forecast the most probable moves of its human opponent and adjust itself accordingly.
In October, the programme won a five-game match against Fan Hui, a top European player, ranked well below Lee internationally.
The five games between Lee and AlphaGo will be played from March 9 to 15 in Seoul and will be streamed on YouTube.