diff --git a/checkout.py b/checkout.py
index 217a5a5a4..03e28f68c 100644
--- a/checkout.py
+++ b/checkout.py
@@ -343,7 +343,13 @@ class SvnCheckout(CheckoutBase, SvnMixIn):
               self._check_output_svn(
                   ['copy', p.source_filename, p.filename])
             if p.diff_hunks:
-              cmd = ['patch', '-p%s' % p.patchlevel, '--forward', '--force']
+              cmd = [
+                'patch',
+                '-p%s' % p.patchlevel,
+                '--forward',
+                '--force',
+                '--no-backup-if-mismatch',
+              ]
               stdout += subprocess2.check_output(
                   cmd, stdin=p.get(False), cwd=self.project_path)
             elif p.is_new and not os.path.exists(filepath):
diff --git a/tests/checkout_test.py b/tests/checkout_test.py
index 31e1f4f1f..1c4d7fdd5 100755
--- a/tests/checkout_test.py
+++ b/tests/checkout_test.py
@@ -307,7 +307,7 @@ class SvnCheckout(SvnBaseTest):
   def testException(self):
     self._check_exception(
         self._get_co(None),
-        'While running patch -p1 --forward --force;\n'
+        'While running patch -p1 --forward --force --no-backup-if-mismatch;\n'
         'patching file chrome/file.cc\n'
         'Hunk #1 FAILED at 3.\n'
         '1 out of 1 hunk FAILED -- saving rejects to file '
@@ -513,7 +513,7 @@ class ReadOnlyCheckout(SvnBaseTest):
   def testException(self):
     self._check_exception(
         self._get_co(None),
-        'While running patch -p1 --forward --force;\n'
+        'While running patch -p1 --forward --force --no-backup-if-mismatch;\n'
         'patching file chrome/file.cc\n'
         'Hunk #1 FAILED at 3.\n'
         '1 out of 1 hunk FAILED -- saving rejects to file '