diff --git a/tests/test_warp.py b/tests/test_warp.py
index 55f40764c3..0e5f2466db 100644
--- a/tests/test_warp.py
+++ b/tests/test_warp.py
@@ -217,6 +217,7 @@ def itk_warp(img, ddf):
     # warp
     warp_filter.SetDisplacementField(displacement_field)
     warp_filter.SetInput(itk_img)
+    warp_filter.Update()
     warped_img = warp_filter.GetOutput()
     warped_img = np.asarray(warped_img)