diff --git a/lib/mocha/class_methods.rb b/lib/mocha/class_methods.rb
index 2ccd58fd..7b2fc32f 100644
--- a/lib/mocha/class_methods.rb
+++ b/lib/mocha/class_methods.rb
@@ -12,7 +12,7 @@ def initialize(klass)
 
       def mocha(instantiate = true)
         if instantiate
-          @mocha ||= Mocha::Mockery.instance.mock_impersonating_any_instance_of(@stubba_object)
+          @mocha ||= Mocha::Mockery.instance.mock_impersonating_any_instance_of(@stubba_object).responds_like_instance_of(@stubba_object)
         else
           defined?(@mocha) ? @mocha : nil
         end
diff --git a/lib/mocha/mock.rb b/lib/mocha/mock.rb
index b448cfe0..e6e7e873 100644
--- a/lib/mocha/mock.rb
+++ b/lib/mocha/mock.rb
@@ -8,6 +8,7 @@
 require 'mocha/parameters_matcher'
 require 'mocha/argument_iterator'
 require 'mocha/expectation_error_factory'
+require 'mocha/ruby_version'
 
 module Mocha
   # Traditional mock object.
@@ -381,9 +382,13 @@ def raise_unexpected_invocation_error(invocation, matching_expectation)
     end
 
     def check_responder_responds_to(symbol)
-      if @responder && !@responder.respond_to?(symbol) # rubocop:disable Style/GuardClause
-        raise NoMethodError, "undefined method `#{symbol}' for #{mocha_inspect} which responds like #{@responder.mocha_inspect}"
-      end
+      return unless @responder
+
+      legacy_behaviour_for_array_flatten = !RUBY_V23_PLUS && !@responder.respond_to?(symbol) && (symbol == :to_ary)
+
+      return if @responder.respond_to?(symbol, true) && !legacy_behaviour_for_array_flatten
+
+      raise NoMethodError, "undefined method `#{symbol}' for #{mocha_inspect} which responds like #{@responder.mocha_inspect}"
     end
 
     def check_expiry
diff --git a/lib/mocha/object_methods.rb b/lib/mocha/object_methods.rb
index 4e4e5967..045a3317 100644
--- a/lib/mocha/object_methods.rb
+++ b/lib/mocha/object_methods.rb
@@ -14,7 +14,7 @@ module ObjectMethods
     # @private
     def mocha(instantiate = true)
       if instantiate
-        @mocha ||= Mocha::Mockery.instance.mock_impersonating(self)
+        @mocha ||= Mocha::Mockery.instance.mock_impersonating(self).responds_like(self)
       else
         defined?(@mocha) ? @mocha : nil
       end
diff --git a/lib/mocha/ruby_version.rb b/lib/mocha/ruby_version.rb
index 124eb472..3d8e857c 100644
--- a/lib/mocha/ruby_version.rb
+++ b/lib/mocha/ruby_version.rb
@@ -1,3 +1,4 @@
 module Mocha
+  RUBY_V23_PLUS = Gem::Version.new(RUBY_VERSION.dup) >= Gem::Version.new('2.3')
   RUBY_V27_PLUS = Gem::Version.new(RUBY_VERSION.dup) >= Gem::Version.new('2.7')
 end
diff --git a/test/acceptance/responds_like_test.rb b/test/acceptance/responds_like_test.rb
index 35355d3a..1bc85d7c 100644
--- a/test/acceptance/responds_like_test.rb
+++ b/test/acceptance/responds_like_test.rb
@@ -130,14 +130,14 @@ def foo; end
     assert_passed(test_result)
   end
 
-  def test_mock_which_responds_like_object_with_protected_method_raises_no_method_error_when_method_is_not_stubbed
+  def test_mock_which_responds_like_object_with_protected_method_raises_unexpected_invocation_exception_when_method_is_not_stubbed
     object = Class.new do
       def foo; end
       protected :foo
     end.new
     test_result = run_as_test do
       m = mock.responds_like(object)
-      assert_raises(NoMethodError) { m.foo } # vs Minitest::Assertion for public method
+      assert_raises(Minitest::Assertion) { m.foo }
     end
     assert_passed(test_result)
   end
@@ -168,7 +168,7 @@ def foo; end
     assert_passed(test_result)
   end
 
-  def test_mock_which_responds_like_object_with_protected_method_raises_no_method_error_when_method_is_stubbed
+  def test_mock_which_responds_like_object_with_protected_method_does_not_raise_exception_when_method_is_stubbed
     object = Class.new do
       def foo; end
       protected :foo
@@ -176,7 +176,7 @@ def foo; end
     test_result = run_as_test do
       m = mock.responds_like(object)
       m.stubs(:foo)
-      assert_raises(NoMethodError) { m.foo } # vs no exception for public method
+      assert_nil m.foo
     end
     assert_passed(test_result)
   end
@@ -196,14 +196,14 @@ def foo; end
     assert_passed(test_result)
   end
 
-  def test_mock_which_responds_like_object_with_private_method_raises_no_method_error_when_method_is_not_stubbed
+  def test_mock_which_responds_like_object_with_private_method_raises_unexpected_invocation_exception_when_method_is_not_stubbed
     object = Class.new do
       def foo; end
       private :foo
     end.new
     test_result = run_as_test do
       m = mock.responds_like(object)
-      assert_raises(NoMethodError) { m.foo } # vs Minitest::Assertion for public method
+      assert_raises(Minitest::Assertion) { m.foo }
     end
     assert_passed(test_result)
   end
@@ -234,7 +234,7 @@ def foo; end
     assert_passed(test_result)
   end
 
-  def test_mock_which_responds_like_object_with_private_method_raises_no_method_error_when_method_is_stubbed
+  def test_mock_which_responds_like_object_with_private_method_does_not_raise_exception_when_method_is_stubbed
     object = Class.new do
       def foo; end
       private :foo
@@ -242,7 +242,7 @@ def foo; end
     test_result = run_as_test do
       m = mock.responds_like(object)
       m.stubs(:foo)
-      assert_raises(NoMethodError) { m.foo } # vs no exception for public method
+      assert_nil m.foo
     end
     assert_passed(test_result)
   end