diff --git a/tests/rules/test_git_diff_staged.py b/tests/rules/test_git_diff_staged.py
index a4c62a37..364cb267 100644
--- a/tests/rules/test_git_diff_staged.py
+++ b/tests/rules/test_git_diff_staged.py
@@ -3,7 +3,9 @@ from thefuck.rules.git_diff_staged import match, get_new_command
 from tests.utils import Command
 
 
-@pytest.mark.parametrize('command', [Command(script='git diff')])
+@pytest.mark.parametrize('command', [
+    Command(script='git diff foo'),
+    Command(script='git diff')])
 def test_match(command):
     assert match(command, None)
 
@@ -18,6 +20,7 @@ def test_not_match(command):
 
 
 @pytest.mark.parametrize('command, new_command', [
-    (Command('git diff'), 'git diff --staged')])
+    (Command('git diff'), 'git diff --staged'),
+    (Command('git diff foo'), 'git diff --staged foo')])
 def test_get_new_command(command, new_command):
     assert get_new_command(command, None) == new_command
diff --git a/thefuck/rules/git_diff_staged.py b/thefuck/rules/git_diff_staged.py
index a35234e4..c879cf40 100644
--- a/thefuck/rules/git_diff_staged.py
+++ b/thefuck/rules/git_diff_staged.py
@@ -10,4 +10,4 @@ def match(command, settings):
 
 @utils.git_support
 def get_new_command(command, settings):
-    return '{} --staged'.format(command.script)
+    return command.script.replace(' diff', ' diff --staged')