diff --git a/tools/testing/selftests/netfilter/nft_nat.sh b/tools/testing/selftests/netfilter/nft_nat.sh
index da1c1e4b6c86..905c033db74d 100755
--- a/tools/testing/selftests/netfilter/nft_nat.sh
+++ b/tools/testing/selftests/netfilter/nft_nat.sh
@@ -759,14 +759,16 @@ test_port_shadow()
 	local result=""
 	local logmsg=""
 
+	# make shadow entry, from client (ns2), going to (ns1), port 41404, sport 1405.
+	echo "fake-entry" | ip netns exec "$ns2" nc -w 1 -p 1405 -u "$daddrc" 41404 > /dev/null
+
 	echo ROUTER | ip netns exec "$ns0" nc -w 5 -u -l -p 1405 >/dev/null 2>&1 &
 	nc_r=$!
 
 	echo CLIENT | ip netns exec "$ns2" nc -w 5 -u -l -p 1405 >/dev/null 2>&1 &
 	nc_c=$!
 
-	# make shadow entry, from client (ns2), going to (ns1), port 41404, sport 1405.
-	echo "fake-entry" | ip netns exec "$ns2" nc -w 1 -p 1405 -u "$daddrc" 41404 > /dev/null
+	sleep 0.3
 
 	# ns1 tries to connect to ns0:1405.  With default settings this should connect
 	# to client, it matches the conntrack entry created above.