In the ultimate battle of man versus machine, humans are running a close second.
On Saturday, a Google (GOOG) computer clocked its third consecutive victory over Lee Se-dol, the long-reigning global champion of the world's most complex board game. That win makes the machine the clear winner in a best-of-five series.
The achievements of the Google DeepMind computer, AlphaGo, are considered a significant advancement in artificial intelligence.
"To be honest, we are a bit stunned," said Google DeepMind CEO Demis Hassabis, after AlphaGo's third win. "We came here to challenge Lee Se-dol, as we wanted to learn from him and see what AlphaGo was capable of."
Since Wednesday, Lee and AlphaGo have been engaged in these high stakes games in Seoul. But AlphaGo has consistently won each of the games played thus far.
Related: Man vs machine: Google computer wins first match against world 'Go' champion
Lee, who looked a bit glum, said he wasn't "sure what to say."
"I feel kind of powerless," he said to reporters. "Even if I were to go back and redo the first game, I think that I wouldn't have been able to win, because at the time, I misjudged the capabilities of AlphaGo."
Even though the computer is now the clear winner out of the full match, there are two more games to be played in the coming days -- one Sunday, and the last on Tuesday.
Lee, who holds the highest possible professional ranking for a Go player and has been called "the Roger Federer of Go," asked the public to continue to follow the remaining games.
Go originated thousands of years ago in China. During play, two opponents take turns placing black and white stones on a square grid of 19 lines by 19 lines. The goal is to take territorial control of the board by using pieces to surround those of the other player.
Related: Computers will overtake us when they learn to love, says futurist
Games can last for hours, and winning requires immense mental stamina, intuition and strategy.
Teaching computers to master Go has been a kind of holy grail for artificial intelligence scientists. There are more possible configurations of the board than atoms in the universe, according to Demis Hassabis, CEO of Google DeepMind, which developed AlphaGo.
"Go is the most profound game that mankind has ever devised," Hassabis said, before the games against Lee started. "Go is a game primarily about intuition and feel, rather than brute calculation, which is what makes it so hard for computers to play well."
Last October, AlphaGo convincingly defeated the European Go champion, Fan Hui, obliterating him in five consecutive games. The computer's victory was considered a huge breakthrough, occurring roughly a decade sooner than experts had expected.
Software programs long ago became adept at classic board games like backgammon. Their rapid progress culminated in the historic victory of IBM's Deep Blue computer over world chess champion Gary Kasparov in 1997.
Related: Mark Zuckerberg says there's nothing to fear from artificial
But it has taken another two decades for artificial intelligence to get to grips with the mind-boggling complexities of Go. Until recently, software programs could only compete with human amateurs.
Google researchers say they expect AlphaGo's technology will be put to use in the company's own apps, and in areas such as medicine.
Google acquired DeepMind in 2014 to bolster its portfolio in artificial intelligence and robotics.
AlphaGo's wins are an astonishing success for the world of artificial intelligence, but futurist Dr. Michio Kaku said Friday that its simply a "sophisticated adding machine."
Humans will still ultimately win the war against computers, because of things Kaku, and other futurists such as Ray Kurzweil, say can't be computed -- love, leadership skills, innovation and common sense.
"People who are involved with intellectual capital will be the winners of the future," Kaku said.
--With reporting by Hope King in New York
