diff --git a/test/rubygems/rubygems/commands/ins_command.rb b/test/rubygems/rubygems/commands/ins_command.rb
new file mode 100644
index 0000000000..8e2ac16f22
--- /dev/null
+++ b/test/rubygems/rubygems/commands/ins_command.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class Gem::Commands::InsCommand < Gem::Command
+  def initialize
+    super("ins", "Does something different from install", {})
+  end
+end
diff --git a/test/rubygems/test_gem_command_manager.rb b/test/rubygems/test_gem_command_manager.rb
index f04ec0cafa..f3848e498d 100644
--- a/test/rubygems/test_gem_command_manager.rb
+++ b/test/rubygems/test_gem_command_manager.rb
@@ -50,16 +50,17 @@ class TestGemCommandManager < Gem::TestCase
   end
 
   def test_find_command_ambiguous_exact
-    ins_command = Class.new
-    Gem::Commands.send :const_set, :InsCommand, ins_command
+    old_load_path = $:.dup
+    $: << File.expand_path("test/rubygems", PROJECT_DIR)
 
     @command_manager.register_command :ins
 
     command = @command_manager.find_command "ins"
 
-    assert_kind_of ins_command, command
+    assert_kind_of Gem::Commands::InsCommand, command
   ensure
-    Gem::Commands.send :remove_const, :InsCommand
+    $:.replace old_load_path
+    @command_manager.unregister_command :ins
   end
 
   def test_find_command_unknown