diff --git a/sdcflows/transform.py b/sdcflows/transform.py
index 6b649013bc..2c132258f5 100644
--- a/sdcflows/transform.py
+++ b/sdcflows/transform.py
@@ -88,7 +88,7 @@ def fit(self, target_reference, affine=None, approx=True):
         # Project the reference's grid onto the fieldmap's
         target_reference = target_reference.__class__(
             target_reference.dataobj,
-            affine @ target_affine.T,
+            affine @ target_affine,
             target_reference.header,
         )