diff --git a/lib/rubygems.rb b/lib/rubygems.rb
index 85790fc181..9440ab048a 100644
--- a/lib/rubygems.rb
+++ b/lib/rubygems.rb
@@ -1303,6 +1303,7 @@ An Array (#{env.inspect}) was passed in from #{caller[3]}
     def remove_unresolved_default_spec(spec)
       spec.files.each do |file|
         @path_to_default_spec_map.delete(file)
+        @path_to_default_spec_map.delete(file.sub(suffix_regexp, ""))
       end
     end
 
diff --git a/test/rubygems/test_require.rb b/test/rubygems/test_require.rb
index dc722f2e0f..b341249391 100644
--- a/test/rubygems/test_require.rb
+++ b/test/rubygems/test_require.rb
@@ -41,6 +41,10 @@ class TestGemRequire < Gem::TestCase
     assert require(path), "'#{path}' was already required"
   end
 
+  def refute_require(path)
+    refute require(path), "'#{path}' was not yet required"
+  end
+
   # Providing -I on the commandline should always beat gems
   def test_dash_i_beats_gems
     a1 = util_spec "a", "1", {"b" => "= 1"}, "lib/test_gem_require_a.rb"
@@ -334,6 +338,22 @@ class TestGemRequire < Gem::TestCase
     assert_equal %w(default-2.0.0.0), loaded_spec_names
   end
 
+  def test_default_gem_require_activates_just_once
+    default_gem_spec = new_default_spec("default", "2.0.0.0",
+                                        nil, "default/gem.rb")
+    install_default_specs(default_gem_spec)
+
+    assert_require "default/gem"
+
+    times_called = 0
+
+    Kernel.stub(:gem, ->(name, requirement) { times_called += 1 }) do
+      refute_require "default/gem"
+    end
+
+    assert_equal 0, times_called
+  end
+
   def test_realworld_default_gem
     begin
       gem 'json'