diff --git a/src/core/tcp_out.c b/src/core/tcp_out.c
index da5e7e4a..feb6c7ea 100644
--- a/src/core/tcp_out.c
+++ b/src/core/tcp_out.c
@@ -1597,6 +1597,7 @@ tcp_zero_window_probe(struct tcp_pcb *pcb)
     NETIF_SET_HWADDRHINT(netif, &(pcb->addr_hint));
     err = ip_output_if(PCB_ISIPV6(pcb), p, &pcb->local_ip, &pcb->remote_ip, pcb->ttl,
       0, IP_PROTO_TCP, netif);
+    NETIF_SET_HWADDRHINT(netif, NULL);
   }
 
   pbuf_free(p);