diff --git a/fsl/wrappers/wrapperutils.py b/fsl/wrappers/wrapperutils.py
index 260841d4b90f6386a9070c02a8aae474685b3749..aab71b90c0afe6ef0e0b369f0d6f830b3be3f511 100644
--- a/fsl/wrappers/wrapperutils.py
+++ b/fsl/wrappers/wrapperutils.py
@@ -1046,7 +1046,7 @@ def fileOrImage(*args, **kwargs):
 
             # in-memory image - we have
             # to save it out to a file
-            if infile is None:
+            if infile is None or not op.exists(infile):
                 hd, infile = tempfile.mkstemp(fslimage.defaultExt(),
                                               dir=workdir)
                 os.close(hd)