diff --git a/autoload/fugitive.vim b/autoload/fugitive.vim
index 12cd3ac..1b8afe3 100644
--- a/autoload/fugitive.vim
+++ b/autoload/fugitive.vim
@@ -218,7 +218,7 @@ function! s:Map(mode, lhs, rhs, ...) abort
       let tail = matchstr(head, '<[^<>]*>$\|.$') . tail
       let head = substitute(head, '<[^<>]*>$\|.$', '', '')
     endwhile
-    if !skip && flags !~# '<unique>' || empty(mapcheck(head.tail, mode))
+    if !skip && (flags !~# '<unique>' || empty(mapcheck(head.tail, mode)))
       call add(maps, mode.'map <buffer>' . s:nowait . flags . ' ' . head.tail . ' ' . a:rhs)
       if a:0 > 1
         let b:undo_ftplugin = get(b:, 'undo_ftplugin', 'exe') .