diff --git a/plugin/fugitive.vim b/plugin/fugitive.vim
index a67f190..ae4de11 100644
--- a/plugin/fugitive.vim
+++ b/plugin/fugitive.vim
@@ -996,7 +996,7 @@ endfunction
 " }}}1
 " Gdiff {{{1
 
-call s:command("-bar -nargs=? -complete=customlist,s:EditComplete Gdiff :execute s:Diff(<f-args>)")
+call s:command("-bang -bar -nargs=? -complete=customlist,s:EditComplete Gdiff :execute s:Diff(<bang>0,<f-args>)")
 
 augroup fugitive_diff
   autocmd BufWinLeave * if winnr('$') == 2 && &diff && getbufvar(+expand('<abuf>'), 'git_dir') !=# '' | diffoff! | endif
@@ -1025,14 +1025,15 @@ endfunction
 
 call s:add_methods('buffer',['compare_age'])
 
-function! s:Diff(...) abort
+function! s:Diff(bang,...) abort
+  let split = a:bang ? 'split' : 'vsplit'
   if exists(':DiffGitCached')
     return 'DiffGitCached'
   elseif (!a:0 || a:1 == ':') && s:buffer().commit() =~# '^[0-1]\=$' && s:repo().git_chomp_in_tree('ls-files', '--unmerged', '--', s:buffer().path()) !=# ''
-      leftabove vsplit `=fugitive#buffer().repo().translate(s:buffer().expand(':2'))`
+      execute 'leftabove '.split.' `=fugitive#buffer().repo().translate(s:buffer().expand('':2''))`'
       diffthis
       wincmd p
-      rightbelow vsplit `=fugitive#buffer().repo().translate(s:buffer().expand(':3'))`
+      execute 'rightbelow '.split.' `=fugitive#buffer().repo().translate(s:buffer().expand('':3''))`'
       diffthis
       wincmd p
       diffthis
@@ -1063,9 +1064,9 @@ function! s:Diff(...) abort
     let spec = s:repo().translate(file)
     let commit = matchstr(spec,'\C[^:/]//\zs\x\+')
     if s:buffer().compare_age(commit) < 0
-      rightbelow vsplit `=spec`
+      execute 'rightbelow '.split.' `=spec`'
     else
-      leftabove vsplit `=spec`
+      execute 'leftabove '.split.' `=spec`'
     endif
     diffthis
     wincmd p