diff --git a/asdf-support.lisp b/asdf-support.lisp
index cb1b158e5a70a5db558bf0ea15573e9a7578e237..f6ebe3f418a4031cf96a5b62931bd9f48dc4e725 100644
--- a/asdf-support.lisp
+++ b/asdf-support.lisp
@@ -259,7 +259,10 @@
 (defun do-process-import (import
                           &key (search-path *protobuf-search-path*)
                                (output-path *protobuf-output-path*))
-  (dolist (path search-path (error "Could not import ~S" import))
+  (dolist (path (or search-path
+                    ;; Fallback in case someone is playing with 'parse-schema' by hand
+                    (and (asdf:absolute-pathname-p import) (list (directory-namestring import))))
+           (error "Could not import ~S" import))
     (let* ((proto-file (asdf::merge-pathnames* import path))
            (lisp-file (if output-path
                         (asdf::lispize-pathname