South Korean professional Go player Lee Sedol (R) shakes hands with Demis Hassabis(L), the CEO of Google's London-based AI company DeepMind during a press conference after finishing the final match of the Google DeepMind Challenge Match against Google's artificial intelligence program, AlphaGo. [Photo/Xinhua]

About four and a half hours into the match, AlphaGo had been subject to the one-minute countdown for the first time as the Go-playing AI consumed all of the given two-hour time limit.

AlphaGo made a very rapid decision on moves, in which human Go players tend to take very long, but the computer program took a long time to make moves that humans think of as easy to determine, according to commentators.

Playing black, Lee put his first two stones right beside flower spots in the right side, while AlphaGo placed its first two white stones in flowers in the left side.