diff --git a/git-gui.sh b/git-gui.sh
index 85fbc021fe..549f59ba73 100755
--- a/git-gui.sh
+++ b/git-gui.sh
@@ -388,6 +388,9 @@ proc _lappend_nice {cmd_var} {
 
 	if {![info exists _nice]} {
 		set _nice [_which nice]
+		if {[catch {exec $_nice git version}]} {
+			set _nice {}
+		}
 	}
 	if {$_nice ne {}} {
 		lappend cmd $_nice