Google's artificial intelligence software has beaten Chinese Go master Ke Jie for a second time, taking an unassailable 2-0 lead in a series meant to test the limits of computers in taking on humans at complex tasks.
Go is a ancient, highly complex board game that involves two contestants placing black and white stones on a grid.
It is popular in Asian countries and most top-ranked players hail from China, Japan and South Korea.
Ke, the 19-year-old world No.1, was visibly frustrated on Thursday, tugging his hair and laying his head on the table during the final moments of the second match against Google's Go-playing software AlphaGo.
"Last year, I think the way AlphaGo played was pretty close to human beings but today I think he plays like the God of Go," Ke said after the game in the eastern Chinese river town of Wuzhen.
Following his defeat in the first match of the best-of-three series on Tuesday, Ke said he would not compete against AI again due to its rapid improvement.
The victory over the world's top player, which many thought would take decades to achieve, comes after the AI program from Google's DeepMind unit bested a South Korean Go professional in a similar exhibition match in 2016.
