diff --git a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ads/ServerSideAdInsertionMediaSource.java b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ads/ServerSideAdInsertionMediaSource.java
index 21d9bda7d8..296cc3a3a6 100644
--- a/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ads/ServerSideAdInsertionMediaSource.java
+++ b/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/source/ads/ServerSideAdInsertionMediaSource.java
@@ -188,6 +188,7 @@ public final class ServerSideAdInsertionMediaSource extends BaseMediaSource
       if (playbackHandler == null) {
         this.adPlaybackStates = adPlaybackStates;
       } else {
+        Timeline finalContentTimeline = contentTimeline;
         playbackHandler.post(
             () -> {
               for (SharedMediaPeriod mediaPeriod : mediaPeriods.values()) {
@@ -206,9 +207,9 @@ public final class ServerSideAdInsertionMediaSource extends BaseMediaSource
                 }
               }
               this.adPlaybackStates = adPlaybackStates;
-              if (contentTimeline != null) {
+              if (finalContentTimeline != null) {
                 refreshSourceInfo(
-                    new ServerSideAdInsertionTimeline(contentTimeline, adPlaybackStates));
+                    new ServerSideAdInsertionTimeline(finalContentTimeline, adPlaybackStates));
               }
             });
       }