diff --git a/actionpack/lib/action_dispatch/middleware/static.rb b/actionpack/lib/action_dispatch/middleware/static.rb
index 360c1209bb3fef8490ba5fbb4c8e81edbdbc51b7..404943d720302f5378dc8b251a872e31a8819bdb 100644
--- a/actionpack/lib/action_dispatch/middleware/static.rb
+++ b/actionpack/lib/action_dispatch/middleware/static.rb
@@ -35,18 +35,15 @@ def ext
   end
 
   class Static
-    FILE_METHODS = %w(GET HEAD).freeze
-
     def initialize(app, path, cache_control=nil)
       @app = app
       @file_handler = FileHandler.new(path, cache_control)
     end
 
     def call(env)
-      path   = env['PATH_INFO'].chomp('/')
-      method = env['REQUEST_METHOD']
-
-      if FILE_METHODS.include?(method)
+      case env['REQUEST_METHOD']
+      when 'GET', 'HEAD'
+        path = env['PATH_INFO'].chomp('/')
         if match = @file_handler.match?(path)
           env["PATH_INFO"] = match
           return @file_handler.call(env)