diff --git a/library/core/src/main/java/com/google/android/exoplayer2/source/ProgressiveMediaSource.java b/library/core/src/main/java/com/google/android/exoplayer2/source/ProgressiveMediaSource.java
index 259f293a94..6c1d26cb07 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/source/ProgressiveMediaSource.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/source/ProgressiveMediaSource.java
@@ -180,15 +180,18 @@ public final class ProgressiveMediaSource extends BaseMediaSource
     @Override
     public ProgressiveMediaSource createMediaSource(MediaItem mediaItem) {
       checkNotNull(mediaItem.playbackProperties);
-      MediaItem.Builder builder = mediaItem.buildUpon();
-      if (mediaItem.playbackProperties.tag == null) {
-        builder.setTag(tag);
-      }
-      if (mediaItem.playbackProperties.customCacheKey == null) {
-        builder.setCustomCacheKey(customCacheKey);
+      boolean needsTag = mediaItem.playbackProperties.tag == null && tag != null;
+      boolean needsCustomCacheKey =
+          mediaItem.playbackProperties.customCacheKey == null && customCacheKey != null;
+      if (needsTag && needsCustomCacheKey) {
+        mediaItem = mediaItem.buildUpon().setTag(tag).setCustomCacheKey(customCacheKey).build();
+      } else if (needsTag) {
+        mediaItem = mediaItem.buildUpon().setTag(tag).build();
+      } else if (needsCustomCacheKey) {
+        mediaItem = mediaItem.buildUpon().setCustomCacheKey(customCacheKey).build();
       }
       return new ProgressiveMediaSource(
-          builder.build(),
+          mediaItem,
           dataSourceFactory,
           extractorsFactory,
           drmSessionManager,