Index: lucene/core/src/java/org/apache/lucene/search/NRTManager.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/search/NRTManager.java	(revision 1353141)
+++ lucene/core/src/java/org/apache/lucene/search/NRTManager.java	(working copy)
@@ -28,6 +28,7 @@
 import org.apache.lucene.analysis.Analyzer;
 import org.apache.lucene.index.CorruptIndexException;
 import org.apache.lucene.index.DirectoryReader;
+import org.apache.lucene.index.SegmentInfoPerCommit;
 import org.apache.lucene.index.IndexReader; // javadocs
 import org.apache.lucene.index.IndexWriter;
 import org.apache.lucene.index.IndexableField;
@@ -255,6 +256,14 @@
     long getAndIncrementGeneration() {
       return indexingGen.getAndIncrement();
     }
+
+    public long tryDeleteDocument(SegmentInfoPerCommit info, int docID) throws IOException {
+      if (writer.tryDeleteDocument(info, docID)) {
+        return indexingGen.get();
+      } else {
+        return -1;
+      }
+    }
   }
 
   /**
Index: lucene/core/src/java/org/apache/lucene/index/SegmentReader.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/index/SegmentReader.java	(revision 1353141)
+++ lucene/core/src/java/org/apache/lucene/index/SegmentReader.java	(working copy)
@@ -194,7 +194,8 @@
   /**
    * Return the SegmentInfoPerCommit of the segment this reader is reading.
    */
-  SegmentInfoPerCommit getSegmentInfo() {
+  // nocmmit public
+  public SegmentInfoPerCommit getSegmentInfo() {
     return si;
   }
 
Index: lucene/core/src/java/org/apache/lucene/index/IndexWriter.java
===================================================================
--- lucene/core/src/java/org/apache/lucene/index/IndexWriter.java	(revision 1353141)
+++ lucene/core/src/java/org/apache/lucene/index/IndexWriter.java	(working copy)
@@ -1216,6 +1216,26 @@
     }
   }
 
+  public synchronized boolean tryDeleteDocument(SegmentInfoPerCommit info, int docID) throws IOException {
+    if (segmentInfos.indexOf(info) != -1) {
+      ReadersAndLiveDocs rld = readerPool.get(info, false);
+      if (rld != null) {
+        synchronized(bufferedDeletesStream) {
+          rld.initWritableLiveDocs();
+          rld.delete(docID);
+          // nocommit droip 100% deleted seg?
+          //System.out.println("  yes " + info.info.name + " " + docID);
+          return true;
+        }
+      } else {
+        //System.out.println("  no rld " + info.info.name + " " + docID);
+      }
+    } else {
+      //System.out.println("  no seg " + info.info.name + " " + docID);
+    }
+    return false;
+  }
+
   /**
    * Deletes the document(s) containing any of the
    * terms. All given deletes are applied and flushed atomically