diff --git a/autoload/fugitive.vim b/autoload/fugitive.vim
index 57cdc67..59731ef 100644
--- a/autoload/fugitive.vim
+++ b/autoload/fugitive.vim
@@ -4172,6 +4172,11 @@ function! s:GrepSubcommand(line1, line2, range, bang, mods, options) abort
   endif
 endfunction
 
+function! fugitive#GrepCommand(line1, line2, range, bang, mods, arg) abort
+  return fugitive#Command(a:line1, a:line2, a:range, a:bang, a:mods,
+        \ "grep -O " . a:arg)
+endfunction
+
 let s:log_diff_context = '{"filename": fugitive#Find(v:val . from, a:dir), "lnum": get(offsets, v:key), "module": strpart(v:val, 0, len(a:state.base_module)) . from}'
 
 function! s:LogFlushQueue(state, dir) abort
diff --git a/plugin/fugitive.vim b/plugin/fugitive.vim
index 21577de..2b9e4d9 100644
--- a/plugin/fugitive.vim
+++ b/plugin/fugitive.vim
@@ -437,9 +437,9 @@ unlet s:cmd
 exe "command! -bar -bang -nargs=? -complete=customlist,fugitive#CdComplete Gcd  exe fugitive#Cd(<q-args>, 0)"
 exe "command! -bar -bang -nargs=? -complete=customlist,fugitive#CdComplete Glcd exe fugitive#Cd(<q-args>, 1)"
 
-exe 'command! -bang -nargs=? -range=-1' s:addr_wins '-complete=customlist,fugitive#GrepComplete Ggrep  exe fugitive#Command(<line1>, <count>, +"<range>", <bang>0, "<mods>", "grep -O " . <q-args>)'
-exe 'command! -bang -nargs=? -range=-1' s:addr_wins '-complete=customlist,fugitive#GrepComplete Gcgrep exe fugitive#Command(<line1>, <count>, +"<range>", <bang>0, "<mods>", "grep -O " . <q-args>)'
-exe 'command! -bang -nargs=? -range=-1' s:addr_wins '-complete=customlist,fugitive#GrepComplete Glgrep exe fugitive#Command(0, <count> > 0 ? <count> : 0, +"<range>", <bang>0, "<mods>", "grep -O " . <q-args>)'
+exe 'command! -bang -nargs=? -range=-1' s:addr_wins '-complete=customlist,fugitive#GrepComplete Ggrep  exe fugitive#GrepCommand(<line1>, <count>, +"<range>", <bang>0, "<mods>", <q-args>)'
+exe 'command! -bang -nargs=? -range=-1' s:addr_wins '-complete=customlist,fugitive#GrepComplete Gcgrep exe fugitive#GrepCommand(<line1>, <count>, +"<range>", <bang>0, "<mods>", <q-args>)'
+exe 'command! -bang -nargs=? -range=-1' s:addr_wins '-complete=customlist,fugitive#GrepComplete Glgrep exe fugitive#GrepCommand(0, <count> > 0 ? <count> : 0, +"<range>", <bang>0, "<mods>", <q-args>)'
 
 exe 'command! -bang -nargs=? -range=-1 -complete=customlist,fugitive#LogComplete Glog  :exe fugitive#LogCommand(<line1>,<count>,+"<range>",<bang>0,"<mods>",<q-args>, "")'
 exe 'command! -bang -nargs=? -range=-1 -complete=customlist,fugitive#LogComplete Gclog :exe fugitive#LogCommand(<line1>,<count>,+"<range>",<bang>0,"<mods>",<q-args>, "c")'