diff --git a/library/core/src/main/java/com/google/android/exoplayer2/source/ads/AdPlaybackState.java b/library/core/src/main/java/com/google/android/exoplayer2/source/ads/AdPlaybackState.java
index 70128c78bf..3a093ca79f 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/source/ads/AdPlaybackState.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/source/ads/AdPlaybackState.java
@@ -270,7 +270,9 @@ public final class AdPlaybackState {
   public final AdGroup[] adGroups;
   /** The position offset in the first unplayed ad at which to begin playback, in microseconds. */
   public final long adResumePositionUs;
-  /** The content duration in microseconds, if known. {@link C#TIME_UNSET} otherwise. */
+  /**
+   * The duration of the content period in microseconds, if known. {@link C#TIME_UNSET} otherwise.
+   */
   public final long contentDurationUs;
 
   /**
diff --git a/library/core/src/main/java/com/google/android/exoplayer2/source/ads/SinglePeriodAdTimeline.java b/library/core/src/main/java/com/google/android/exoplayer2/source/ads/SinglePeriodAdTimeline.java
index b5167dc173..cc82510a29 100644
--- a/library/core/src/main/java/com/google/android/exoplayer2/source/ads/SinglePeriodAdTimeline.java
+++ b/library/core/src/main/java/com/google/android/exoplayer2/source/ads/SinglePeriodAdTimeline.java
@@ -44,23 +44,16 @@ public final class SinglePeriodAdTimeline extends ForwardingTimeline {
   @Override
   public Period getPeriod(int periodIndex, Period period, boolean setIds) {
     timeline.getPeriod(periodIndex, period, setIds);
+    long durationUs =
+        period.durationUs == C.TIME_UNSET ? adPlaybackState.contentDurationUs : period.durationUs;
     period.set(
         period.id,
         period.uid,
         period.windowIndex,
-        period.durationUs,
+        durationUs,
         period.getPositionInWindowUs(),
         adPlaybackState);
     return period;
   }
 
-  @Override
-  public Window getWindow(int windowIndex, Window window, long defaultPositionProjectionUs) {
-    window = super.getWindow(windowIndex, window, defaultPositionProjectionUs);
-    if (window.durationUs == C.TIME_UNSET) {
-      window.durationUs = adPlaybackState.contentDurationUs;
-    }
-    return window;
-  }
-
 }