diff --git a/config/flay.yml b/config/flay.yml
index cb7eb82bf..09a2c4f72 100644
--- a/config/flay.yml
+++ b/config/flay.yml
@@ -1,3 +1,3 @@
 ---
 threshold: 16
-total_score: 1321
+total_score: 1316
diff --git a/lib/mutant/mutator/node/send.rb b/lib/mutant/mutator/node/send.rb
index 5d047193e..3dd6a03dc 100644
--- a/lib/mutant/mutator/node/send.rb
+++ b/lib/mutant/mutator/node/send.rb
@@ -182,7 +182,7 @@ def emit_drop_mutation
         #
         # @return [undefined]
         def emit_integer_mutation
-          return unless selector.equal?(:to_i)
+          return unless receiver && selector.equal?(:to_i)
 
           emit(s(:send, nil, :Integer, receiver))
         end
diff --git a/meta/send.rb b/meta/send.rb
index 1870e4aed..ef9837d8b 100644
--- a/meta/send.rb
+++ b/meta/send.rb
@@ -135,6 +135,13 @@
   mutation 'map'
 end
 
+Mutant::Meta::Example.add :send do
+  source 'to_i'
+
+  singleton_mutations
+  mutation 'to_int'
+end
+
 Mutant::Meta::Example.add :send do
   source 'foo.to_s'