diff --git a/src/xprt_quic.c b/src/xprt_quic.c
index d688f20b3..b43e65edf 100644
--- a/src/xprt_quic.c
+++ b/src/xprt_quic.c
@@ -3012,6 +3012,9 @@ static int qc_prep_app_pkts(struct quic_conn *qc, struct qring *qr,
 		if (!pkt)
 			goto err;
 
+		if (qc->flags & QUIC_FL_CONN_RETRANS_OLD_DATA)
+			pkt->flags |= QUIC_FL_TX_PACKET_PROBE_WITH_OLD_DATA;
+
 		total += pkt->len;
 		/* Set the current datagram as prepared into <cbuf>. */
 		qc_set_dg(cbuf, pkt->len, pkt);
@@ -3133,6 +3136,9 @@ static int qc_prep_pkts(struct quic_conn *qc, struct qring *qr,
 		if (!cur_pkt)
 			goto err;
 
+		if (qc->flags & QUIC_FL_CONN_RETRANS_OLD_DATA)
+			cur_pkt->flags |= QUIC_FL_TX_PACKET_PROBE_WITH_OLD_DATA;
+
 		total += cur_pkt->len;
 		/* keep trace of the first packet in the datagram */
 		if (!first_pkt)