IGS 7d vs 6d: KataGo's Verdict on Move 173 Collapse

Two strong players battle to a razor-thin finish on IGS — 31 live spectators watched as Black held a commanding 75% advantage deep into the endgame. Then move 173 happened: G12 instead of M14. KataGo's post-game analysis reveals the single decision that flipped everything, dropping Black's win probability from 75% to 13% in one stone. White closes out by 4.5 points after 257 moves. The pressure of a live audience, a narrow margin, and one critical reading mistake — if you were in that position, you'd probably play the same way.