diff --git a/lucene/CHANGES.txt b/lucene/CHANGES.txt
index b4757401478..072cdd2e352 100644
--- a/lucene/CHANGES.txt
+++ b/lucene/CHANGES.txt
@@ -101,6 +101,12 @@ Bug fixes
 * LUCENE-5285: Improved highlighting of multi-valued fields with
   FastVectorHighlighter. (Nik Everett via Adrien Grand)
 
+Changes in Runtime Behavior
+
+* LUCENE-5362: IndexReader and SegmentCoreReaders now throw 
+  AlreadyClosedException if the refCount in incremented but
+  is less that 1. (Simon Willnauer) 
+
 ======================= Lucene 4.6.0 =======================
 
 New Features
diff --git a/lucene/core/src/java/org/apache/lucene/index/IndexReader.java b/lucene/core/src/java/org/apache/lucene/index/IndexReader.java
index 70174d5f23f..b416812fa55 100644
--- a/lucene/core/src/java/org/apache/lucene/index/IndexReader.java
+++ b/lucene/core/src/java/org/apache/lucene/index/IndexReader.java
@@ -168,8 +168,9 @@ public abstract class IndexReader implements Closeable {
    * @see #tryIncRef
    */
   public final void incRef() {
-    ensureOpen();
-    refCount.incrementAndGet();
+    if (!tryIncRef()) {
+       ensureOpen();
+    }
   }
   
   /**
diff --git a/lucene/core/src/java/org/apache/lucene/index/SegmentCoreReaders.java b/lucene/core/src/java/org/apache/lucene/index/SegmentCoreReaders.java
index 99d96570163..057c98dff51 100644
--- a/lucene/core/src/java/org/apache/lucene/index/SegmentCoreReaders.java
+++ b/lucene/core/src/java/org/apache/lucene/index/SegmentCoreReaders.java
@@ -32,6 +32,7 @@ import org.apache.lucene.codecs.PostingsFormat;
 import org.apache.lucene.codecs.StoredFieldsReader;
 import org.apache.lucene.codecs.TermVectorsReader;
 import org.apache.lucene.index.SegmentReader.CoreClosedListener;
+import org.apache.lucene.store.AlreadyClosedException;
 import org.apache.lucene.store.CompoundFileDirectory;
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.IOContext;
@@ -139,7 +140,13 @@ final class SegmentCoreReaders {
   }
   
   void incRef() {
-    ref.incrementAndGet();
+    int count;
+    while ((count = ref.get()) > 0) {
+      if (ref.compareAndSet(count, count+1)) {
+        return;
+      }
+    }
+    throw new AlreadyClosedException("SegmentCoreReaders is already closed");
   }
 
   NumericDocValues getNormValues(FieldInfo fi) throws IOException {