diff --git a/libavformat/utils.c b/libavformat/utils.c
index 5bc79f4350..e348fbde5a 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -1184,6 +1184,7 @@ static int parse_packet(AVFormatContext *s, AVPacket *pkt, int stream_index)
                                pkt->pts, pkt->dts, pkt->pos);
 
         pkt->pts = pkt->dts = AV_NOPTS_VALUE;
+        pkt->pos = -1;
         /* increment read pointer */
         data += len;
         size -= len;