diff --git a/python/dune/perftool/ufl/transformations/reindexing.py b/python/dune/perftool/ufl/transformations/reindexing.py
index 0b405005d469d904d74d6f57df66e4c3adf6a321..16cc9163530366a812875f3bb9100a5eb0191c20 100644
--- a/python/dune/perftool/ufl/transformations/reindexing.py
+++ b/python/dune/perftool/ufl/transformations/reindexing.py
@@ -47,13 +47,12 @@ class ReindexingMapper(MultiFunction):
         MultiFunction.__init__(self)
         self.replacement_map = {}
         self.multi_index_cache = {}
-        self.im = IndexedMapper(self)
 
     def expr(self, o):
         return self.reuse_if_untouched(o, *tuple(self.call(op) for op in o.ufl_operands))
 
     def indexed(self, o):
-        return self.im(o)
+        return IndexedMapper(self)(o)
 
     def multi_index(self, o):
         newindices = tuple(self.replacement_map.get(i, i) for i in o)