diff --git a/selekt-java/src/main/kotlin/com/bloomberg/selekt/pools/Mutex.kt b/selekt-java/src/main/kotlin/com/bloomberg/selekt/pools/Mutex.kt
index 290f8791d1..716674bf87 100644
--- a/selekt-java/src/main/kotlin/com/bloomberg/selekt/pools/Mutex.kt
+++ b/selekt-java/src/main/kotlin/com/bloomberg/selekt/pools/Mutex.kt
@@ -52,7 +52,7 @@ internal class Mutex {
     }
 
     fun unlock() {
-        isLockedUpdater.set(this, 0)
+        isLockedUpdater[this] = 0
         LockSupport.unpark(waiters.peek())
     }