AlphaGo has again defeated Ke Jie, the world’s number one Go player, in their second game, meaning the AI has secured victory in the three-part match. The win over Ke, universally considered the best Go player in the world, essentially confirms that AlphaGo has surpassed human Go ability a little over a year after the AI first beat Lee Se-dol. 

Ke played “perfectly” for about the first 50 moves, according to AlphaGo’s analysis, and evolved his strategy to engage in a series of complex battles across the board. But AlphaGo handled the multi-angled assault well to simplify the engrossing game and eventually forced Ke to resign. “For the first 100 moves it was the closest we’ve ever seen anyone play against the Master version of AlphaGo,” DeepMind CEO Demis Hassabis said in the post-game press conference.

“Today’s game was different from the first,” Ke said. “AlphaGo made some moves which were opposite from my vision of how to maximize the possibility of winning. I also thought I was very close to winning the game in the middle but maybe that’s not what AlphaGo was thinking. I’m a little bit sad, it’s a bit of a regret because I think I played pretty well.”

Developed by DeepMind, the British company acquired by Google in 2014, the AlphaGo AI uses machine learning and neural networks to analyze its probability of winning and pick moves that are likely to lead to success. Until AlphaGo beat Lee, solving the ancient Chinese board game of Go had long been a north star for computer scientists due to its unparalleled complexity and huge number of potential moves. DeepMind’s success came decades earlier than many had predicted, and the new Master version of AlphaGo is more powerful still.

Ke and AlphaGo are facing off as part of the Future of Go Summit being held by Google in Wuzhen, China this week. The final game will be on Saturday, while Friday will see AlphaGo further put to the test in two stipulation matches; one where it acts as a teammate to two Chinese pros playing each other, and another where it takes on five Chinese pros all at once.