diff --git a/zfs-snapshot-backup.py b/zfs-snapshot-backup.py
index 2fc6319..d9e0e1a 100755
--- a/zfs-snapshot-backup.py
+++ b/zfs-snapshot-backup.py
@@ -63,7 +63,7 @@ def gzip_filename(current, last=None):
     if last is None:
         return f"{current_name}.gz"
     else:
-        last_name = snapshot_name(last)
+        last_name = snapshot_short_name(last)
         return f"{last_name}.to.{current_name}.gz"