diff --git a/include/haproxy/xprt_qstrm.h b/include/haproxy/xprt_qstrm.h
index 5a992f21f..f8af655b8 100644
--- a/include/haproxy/xprt_qstrm.h
+++ b/include/haproxy/xprt_qstrm.h
@@ -4,7 +4,6 @@
 const struct quic_transport_params *xprt_qstrm_lparams(const void *context);
 const struct quic_transport_params *xprt_qstrm_rparams(const void *context);
 
-struct buffer *xprt_qstrm_rxbuf(const void *context);
-size_t xprt_qstrm_rxrlen(const void *context);
+size_t xprt_qstrm_xfer_rxbuf(const void *context, struct buffer *out);
 
 #endif /* _HAPROXY_XPRT_QSTRM_H */
diff --git a/src/mux_quic.c b/src/mux_quic.c
index d2a1e6e3a..127ff048b 100644
--- a/src/mux_quic.c
+++ b/src/mux_quic.c
@@ -3847,25 +3847,13 @@ static int qmux_init(struct connection *conn, struct proxy *prx,
 	}
 
 	if (!conn_is_quic(conn)) {
-		struct buffer *xprt_buf;
-
 		qcc->tx.qstrm_buf = BUF_NULL;
 		qcc->rx.qstrm_buf = BUF_NULL;
 
-		/* Retrieve data if xprt read too much */
-		xprt_buf = xprt_qstrm_rxbuf(conn->xprt_ctx);
-		if (unlikely(b_data(xprt_buf))) {
-			b_alloc(&qcc->rx.qstrm_buf, DB_MUX_RX);
-			if (!b_size(&qcc->rx.qstrm_buf)) {
-				TRACE_ERROR("rx qstrm buf alloc failure", QMUX_EV_QCC_NEW);
-				goto err;
-			}
-			b_xfer(&qcc->rx.qstrm_buf, xprt_buf, b_data(xprt_buf));
-			qcc->rx.rlen = xprt_qstrm_rxrlen(conn->xprt_ctx);
-		}
-		else {
-			qcc->rx.rlen = 0;
-		}
+		/* Rx buffer is transfered from xprt layer - necessary if too many data where read */
+		qcc->rx.rlen = xprt_qstrm_xfer_rxbuf(conn->xprt_ctx, &qcc->rx.qstrm_buf);
+		/* Cannot have a non empty record with an empty buffer. */
+		BUG_ON(qcc->rx.rlen && !b_data(&qcc->rx.qstrm_buf));
 	}
 
 	if (conn_is_back(conn)) {
diff --git a/src/xprt_qstrm.c b/src/xprt_qstrm.c
index 6dcac7725..a03f455a8 100644
--- a/src/xprt_qstrm.c
+++ b/src/xprt_qstrm.c
@@ -39,16 +39,16 @@ const struct quic_transport_params *xprt_qstrm_rparams(const void *context)
 	return &ctx->rparams;
 }
 
-/* Returns RX buffer as mutable to allow zero-copy by the caller. */
-struct buffer *xprt_qstrm_rxbuf(void *context)
+/* Transfer Rx buffer into <out>. */
+size_t xprt_qstrm_xfer_rxbuf(void *context, struct buffer *out)
 {
 	struct xprt_qstrm_ctx *ctx = context;
-	return &ctx->rxbuf;
-}
 
-size_t xprt_qstrm_rxrlen(const void *context)
-{
-	const struct xprt_qstrm_ctx *ctx = context;
+	if (b_data(&ctx->rxbuf)) {
+		*out = ctx->rxbuf;
+		ctx->rxbuf = BUF_NULL;
+	}
+
 	return ctx->rxrlen;
 }
 
@@ -221,6 +221,10 @@ struct task *xprt_qstrm_io_cb(struct task *t, void *context, unsigned int state)
 		conn->xprt_ctx = ctx->ctx_lower;
 		conn->xprt = ctx->ops_lower;
 
+		/* MUX layer is responsible to retrieve any remaining data in
+		 * the Rx buffer prior to reset it.
+		 */
+		BUG_ON(b_data(&ctx->rxbuf));
 		b_free(&ctx->rxbuf);
 		b_free(&ctx->txbuf);