diff --git a/sys/netinet/tcp_stacks/rack.c b/sys/netinet/tcp_stacks/rack.c
--- a/sys/netinet/tcp_stacks/rack.c
+++ b/sys/netinet/tcp_stacks/rack.c
@@ -16489,7 +16489,6 @@
 	sb_offset = tp->snd_max - tp->snd_una;
 	th->th_seq = htonl(tp->snd_max);
 	th->th_ack = htonl(tp->rcv_nxt);
-	tcp_set_flags(th, flags);
 	th->th_win = htons((u_short)(rack->r_ctl.fsb.recwin >> tp->rcv_scale));
 	if (th->th_win == 0) {
 		tp->t_sndzerowin++;
@@ -16552,6 +16551,7 @@
 			ip->ip_tos |= ect;
 		}
 	}
+	tcp_set_flags(th, flags);
 	m->m_pkthdr.len = hdrlen + len;	/* in6_cksum() need this */
 #ifdef INET6
 	if (rack->r_is_v6) {