diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index fc0393779c0dfd44cef7bdc3ec9a57e6d8892d52..32fc540ef3ddfc4d1bb33ae75a0e07b555bdc441 100644
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -527,8 +527,6 @@ static int run_and_feed_hook(const char *hook_name, feed_fn feed, void *feed_sta
 	proc.in = -1;
 	proc.stdout_to_stderr = 1;
 
-	prepare_push_cert_sha1(&proc);
-
 	if (use_sideband) {
 		memset(&muxer, 0, sizeof(muxer));
 		muxer.proc = copy_to_sideband;
@@ -539,6 +537,8 @@ static int run_and_feed_hook(const char *hook_name, feed_fn feed, void *feed_sta
 		proc.err = muxer.in;
 	}
 
+	prepare_push_cert_sha1(&proc);
+
 	code = start_command(&proc);
 	if (code) {
 		if (use_sideband)