diff --git a/activerecord/lib/active_record/associations/collection_association.rb b/activerecord/lib/active_record/associations/collection_association.rb
index 55628c81bb..6ba5ba5228 100644
--- a/activerecord/lib/active_record/associations/collection_association.rb
+++ b/activerecord/lib/active_record/associations/collection_association.rb
@@ -383,7 +383,6 @@ module ActiveRecord
               scoped.all
             end
 
-          records = options[:uniq] ? uniq(records) : records
           records.each { |record| set_inverse_instance(record) }
           records
         end