diff --git a/omv_backup.py b/omv_backup.py
index 126d070..4c2d131 100755
--- a/omv_backup.py
+++ b/omv_backup.py
@@ -627,7 +627,7 @@ if _BACKUP:
                     if _EXECUTE:
                         status, output = subprocess.getstatusoutput(cmnd)
                         for f in output.splitlines():
-                            pattern = r"^[0-9]{4}.*"  # regex pattern: string starts with 'abc'
+                            pattern = r"^[0-9]{4}-[0-9]{2}-[0-9]{2}_[0-9]{2}-[0-9]{2}-[0-9]{2}"  # regex pattern: string starts with 'abc'
                             logging.info(f"Checking {f}")
                             if re.match(pattern, f):
                                 logging.info("Match!")