diff --git a/src/lib/iso_ext.pl b/src/lib/iso_ext.pl
index 4d064193..be44099f 100644
--- a/src/lib/iso_ext.pl
+++ b/src/lib/iso_ext.pl
@@ -86,8 +86,8 @@ scc_helper(C, G, Bb) :-
 scc_helper(_, _, Bb) :-
     '$reset_block'(Bb),
     '$get_ball'(Ball),
-    '$call_with_default_policy'(run_cleaners_with_handling),
     '$erase_ball',
+    '$call_with_default_policy'(run_cleaners_with_handling),
     '$call_with_default_policy'(throw(Ball)).
 scc_helper(_, _, _) :-
     '$get_cp'(Cp),