diff --git a/script/pgn_to_plain.py b/script/pgn_to_plain.py
index 61aa9917..5f9300cb 100644
--- a/script/pgn_to_plain.py
+++ b/script/pgn_to_plain.py
@@ -18,7 +18,7 @@ def parse_result(result_str:str, board:chess.Board) -> int:
         if board.turn == chess.WHITE:
             return 1
         else:
-            return 0
+            return -1
     else:
         print("illeagal result", result_str)
         raise ValueError