Hikaru no Go

Synopsis

After finding about the match, Ogata deduces that Toya must have already arranged this in person, assuming Toya knows nothing about how to use the internet. Both Akira and Ogata suspect that Hikaru has a connection to Sai. Toya looked to have the advantage, but Sai found a great move to erase the enemy territory. Eventually, Toya works out that with best play, he would lose by half a point, and had no doubt that Sai would play the best moves. So Toya resigned, while most onlookers thought it was neck-and-neck. Sai finally realizes why he was brought back through Hikaru, finding his time on this world is about to end.

(Source: Wikipedia)