diff --git a/src/main/java/build/buildfarm/cas/cfc/CASFileCache.java b/src/main/java/build/buildfarm/cas/cfc/CASFileCache.java
index a0515d6b1b..38849642ca 100644
--- a/src/main/java/build/buildfarm/cas/cfc/CASFileCache.java
+++ b/src/main/java/build/buildfarm/cas/cfc/CASFileCache.java
@@ -2637,6 +2637,9 @@ private CancellableOutputStream putImpl(
             onInsert,
             isReset);
     if (out == DUPLICATE_OUTPUT_STREAM) {
+      log.log(Level.FINER, format("duplicate output stream, completing %s for %s", key, writeId));
+      writeWinner.get();
+      onInsert.run();
       return null;
     }
     log.log(Level.FINER, format("entry %s is missing, downloading and populating", key));