diff --git a/libavformat/rtsp.c b/libavformat/rtsp.c
index ca9ce7cf21..8ff4de7e1e 100644
--- a/libavformat/rtsp.c
+++ b/libavformat/rtsp.c
@@ -924,11 +924,24 @@ int ff_rtsp_read_reply(AVFormatContext *s, RTSPMessageHeader *reply,
     return 0;
 }
 
-int ff_rtsp_send_cmd_with_content_async(AVFormatContext *s,
-                                        const char *method, const char *url,
-                                        const char *headers,
-                                        const unsigned char *send_content,
-                                        int send_content_length)
+/**
+ * Send a command to the RTSP server without waiting for the reply.
+ *
+ * @param s RTSP (de)muxer context
+ * @param method the method for the request
+ * @param url the target url for the request
+ * @param headers extra header lines to include in the request
+ * @param send_content if non-null, the data to send as request body content
+ * @param send_content_length the length of the send_content data, or 0 if
+ *                            send_content is null
+ *
+ * @return zero if success, nonzero otherwise
+ */
+static int ff_rtsp_send_cmd_with_content_async(AVFormatContext *s,
+                                               const char *method, const char *url,
+                                               const char *headers,
+                                               const unsigned char *send_content,
+                                               int send_content_length)
 {
     RTSPState *rt = s->priv_data;
     char buf[4096], *out_buf;
diff --git a/libavformat/rtsp.h b/libavformat/rtsp.h
index 62bd3a2ecc..f0ead10da5 100644
--- a/libavformat/rtsp.h
+++ b/libavformat/rtsp.h
@@ -371,24 +371,6 @@ void ff_rtsp_parse_line(RTSPMessageHeader *reply, const char *buf,
 extern int rtsp_rtp_port_min;
 extern int rtsp_rtp_port_max;
 
-/**
- * Send a command to the RTSP server without waiting for the reply.
- *
- * @param s RTSP (de)muxer context
- * @param method the method for the request
- * @param url the target url for the request
- * @param headers extra header lines to include in the request
- * @param send_content if non-null, the data to send as request body content
- * @param send_content_length the length of the send_content data, or 0 if
- *                            send_content is null
- *
- * @return zero if success, nonzero otherwise
- */
-int ff_rtsp_send_cmd_with_content_async(AVFormatContext *s,
-                                        const char *method, const char *url,
-                                        const char *headers,
-                                        const unsigned char *send_content,
-                                        int send_content_length);
 /**
  * Send a command to the RTSP server without waiting for the reply.
  *