diff --git a/model_server/accessors.py b/model_server/accessors.py
index 4f122fb13d8022255f5866daef4646dd3940a00e..e634f2f07d7be338d9d7e6526021190001e2d839 100644
--- a/model_server/accessors.py
+++ b/model_server/accessors.py
@@ -115,6 +115,10 @@ class TifSingleSeriesFileAccessor(GenericImageFileAccessor):
             axs.append('C')
             da = np.expand_dims(da, len(da.shape))
 
+        if 'Z' not in axs:
+            axs.append('Z')
+            da = np.expand_dims(da, len(da.shape))
+
         yxcz = np.moveaxis(
             da,
             [axs.index(k) for k in order],