diff --git a/gitk b/gitk
index 85d33abf4abc26276b9af06a9e89851f5f159592..d5db836528df4e89b09844953b7fb920fe0ee073 100755
--- a/gitk
+++ b/gitk
@@ -5920,6 +5920,8 @@ proc mkpatchgo {} {
     set newid [$patchtop.tosha1 get]
     set fname [$patchtop.fname get]
     set cmd [diffcmd [list $oldid $newid] -p]
+    # trim off the initial "|"
+    set cmd [lrange $cmd 1 end]
     lappend cmd >$fname &
     if {[catch {eval exec $cmd} err]} {
 	error_popup "Error creating patch: $err"