diff --git a/server/montytest/api.py b/server/montytest/api.py
index 10768ef2..32afcd66 100644
--- a/server/montytest/api.py
+++ b/server/montytest/api.py
@@ -34,7 +34,7 @@
 according to the route/URL mapping defined in `__init__.py`.
 """
 
-WORKER_VERSION = 20
+WORKER_VERSION = 21
 
 
 @exception_view_config(HTTPException)
diff --git a/worker/games.py b/worker/games.py
index 73c512e9..32a8e007 100644
--- a/worker/games.py
+++ b/worker/games.py
@@ -1519,27 +1519,40 @@ def run_datagen_games(
             close_fds=not IS_WINDOWS,
         ) as p:
             try:
+                # Wait for the process to complete
+                print("Waiting for datagen to finish ... ", flush=True)
+                p.wait(timeout=FASTCHESS_KILL_TIMEOUT)
+
+                if p.returncode != 0:
+                    print(
+                        f"Datagen process exited with code {p.returncode}. Removing binpack.",
+                        flush=True,
+                    )
+                    if games_file.exists():
+                        games_file.unlink()
+                    raise WorkerException(
+                        f"Datagen process exited with non-zero return code: {p.returncode}"
+                    )
+
+                # Call parse_datagen_output only if process succeeded
                 parse_datagen_output(p, tc_factor, result, remote, current_state)
-            except:
+            except subprocess.TimeoutExpired:
+                print("timeout", flush=True)
+                kill_process(p)
+                raise WorkerException("Datagen process timed out and was killed.")
+            except Exception:
                 # Remove the binpack on exception
                 print("Removing binpack", flush=True)
                 if games_file.exists():
                     games_file.unlink()
+            else:
+                print("Datagen finished", flush=True)
             finally:
-                # We nicely ask cutechess-cli to stop.
+                # We nicely ask the monty datagen process to stop.
                 try:
                     send_sigint(p)
                 except Exception as e:
                     print("\nException in send_sigint:\n", e, sep="", file=sys.stderr)
-                # now wait...
-                print("\nWaiting for datagen to finish ... ", end="", flush=True)
-                try:
-                    p.wait(timeout=FASTCHESS_KILL_TIMEOUT)
-                except subprocess.TimeoutExpired:
-                    print("timeout", flush=True)
-                    kill_process(p)
-                else:
-                    print("done", flush=True)
     except (OSError, subprocess.SubprocessError) as e:
         print(
             "Exception starting datagen:\n",
diff --git a/worker/sri.txt b/worker/sri.txt
index e84c8d3a..d6f5c5dc 100644
--- a/worker/sri.txt
+++ b/worker/sri.txt
@@ -1 +1 @@
-{"__version": 20, "updater.py": "gSJX/HbsPwsZnUZaFbAgF0zwWPWXv+LEw9jBhJkxFOrCH9CZS0+4U4nE2fJdeNze", "worker.py": "VgVVa7f6bdHWJU/uKVcAGApcegP/fZwgV45PLSbfGTHUmc66F51hGbGBZZRvhRMM", "games.py": "jdCHJDCixQ9Fa138HXoUcOvvHEAHO7BWq/3XUmr0GYHQ/zlRYyjuSueEQPxkMTg9"}
+{"__version": 21, "updater.py": "gSJX/HbsPwsZnUZaFbAgF0zwWPWXv+LEw9jBhJkxFOrCH9CZS0+4U4nE2fJdeNze", "worker.py": "n3cgpMhYBEOQVvXl+NNEv6YCsbWqbH0jqiDaI5g0yoCot8fEbThrenDdYNMkI+oq", "games.py": "MyB/5iO/R0PEXQOB+ZhACzieuTTRnuGE3gbzvul35gewqG/t58EztU0fY0FYCzOA"}
diff --git a/worker/worker.py b/worker/worker.py
index 70731f06..e7aac5d0 100644
--- a/worker/worker.py
+++ b/worker/worker.py
@@ -69,7 +69,7 @@
 MIN_CARGO_MAJOR = 1
 MIN_CARGO_MINOR = 77
 
-WORKER_VERSION = 20
+WORKER_VERSION = 21
 FILE_LIST = ["updater.py", "worker.py", "games.py"]
 HTTP_TIMEOUT = 30.0
 INITIAL_RETRY_TIME = 15.0