diff --git a/pc/rtc_stats_collector.cc b/pc/rtc_stats_collector.cc
index 4b92fb6a4b..d891733367 100644
--- a/pc/rtc_stats_collector.cc
+++ b/pc/rtc_stats_collector.cc
@@ -97,7 +97,7 @@ std::string RTCMediaStreamTrackStatsIDFromDirectionAndAttachment(
     int attachment_id) {
   char buf[1024];
   rtc::SimpleStringBuilder sb(buf);
-  sb << "RTCMediaStreamTrack_" << direction << "_" << attachment_id;
+  sb << "DEPRECATED_RTCMediaStreamTrack_" << direction << "_" << attachment_id;
   return sb.str();
 }
 
diff --git a/pc/rtc_stats_collector_unittest.cc b/pc/rtc_stats_collector_unittest.cc
index 5fe4fe7a52..2fff71a1ed 100644
--- a/pc/rtc_stats_collector_unittest.cc
+++ b/pc/rtc_stats_collector_unittest.cc
@@ -740,12 +740,12 @@ class RTCStatsCollectorTest : public ::testing::Test {
     // track (sender)
     graph.sender = stats_->SetupLocalTrackAndSender(
         cricket::MEDIA_TYPE_VIDEO, "LocalVideoTrackID", 3, false, 50);
-    graph.sender_track_id = "RTCMediaStreamTrack_sender_" +
+    graph.sender_track_id = "DEPRECATED_RTCMediaStreamTrack_sender_" +
                             rtc::ToString(graph.sender->AttachmentId());
     // track (receiver) and stream (remote stream)
     graph.receiver = stats_->SetupRemoteTrackAndReceiver(
         cricket::MEDIA_TYPE_VIDEO, "RemoteVideoTrackID", "RemoteStreamId", 4);
-    graph.receiver_track_id = "RTCMediaStreamTrack_receiver_" +
+    graph.receiver_track_id = "DEPRECATED_RTCMediaStreamTrack_receiver_" +
                               rtc::ToString(graph.receiver->AttachmentId());
     graph.remote_stream_id = "RTCMediaStream_RemoteStreamId";
     // peer-connection
@@ -853,13 +853,13 @@ class RTCStatsCollectorTest : public ::testing::Test {
     // track (sender)
     graph.sender = stats_->SetupLocalTrackAndSender(
         cricket::MEDIA_TYPE_AUDIO, "LocalAudioTrackID", kLocalSsrc, false, 50);
-    graph.sender_track_id = "RTCMediaStreamTrack_sender_" +
+    graph.sender_track_id = "DEPRECATED_RTCMediaStreamTrack_sender_" +
                             rtc::ToString(graph.sender->AttachmentId());
     // track (receiver) and stream (remote stream)
     graph.receiver = stats_->SetupRemoteTrackAndReceiver(
         cricket::MEDIA_TYPE_AUDIO, "RemoteAudioTrackID", "RemoteStreamId",
         kRemoteSsrc);
-    graph.receiver_track_id = "RTCMediaStreamTrack_receiver_" +
+    graph.receiver_track_id = "DEPRECATED_RTCMediaStreamTrack_receiver_" +
                               rtc::ToString(graph.receiver->AttachmentId());
     graph.remote_stream_id = "RTCMediaStream_RemoteStreamId";
     // peer-connection