diff --git a/games/racecar.py b/games/racecar.py
index 6c08a9d0787c8fa21ea91ad22e925b8c7801bc1b..2ee3bc6f52ba1a2466be53f410f3ba569930191a 100644
--- a/games/racecar.py
+++ b/games/racecar.py
@@ -30,7 +30,7 @@ class MuZeroConfig:
 
 
         ### Self-Play
-        self.num_workers = 5  # Number of simultaneous threads/workers self-playing to feed the replay buffer
+        self.num_workers = 1  # Number of simultaneous threads/workers self-playing to feed the replay buffer
         self.selfplay_on_gpu = False
         self.max_moves = 1000  # Maximum number of moves if game is not finished before
         self.num_simulations = 50  # Number of future moves self-simulated