diff --git a/lucene/core/src/java/org/apache/lucene/index/MultiDocValues.java b/lucene/core/src/java/org/apache/lucene/index/MultiDocValues.java
index 1e6671ea05c..cf425cf7cd7 100644
--- a/lucene/core/src/java/org/apache/lucene/index/MultiDocValues.java
+++ b/lucene/core/src/java/org/apache/lucene/index/MultiDocValues.java
@@ -450,7 +450,7 @@ public class MultiDocValues {
     public int getOrd(int docID) {
       int subIndex = ReaderUtil.subIndex(docID, docStarts);
       int segmentOrd = values[subIndex].getOrd(docID - docStarts[subIndex]);
-      return (int) mapping.getGlobalOrd(subIndex, segmentOrd);
+      return segmentOrd == -1 ? segmentOrd : (int) mapping.getGlobalOrd(subIndex, segmentOrd);
     }
  
     @Override
diff --git a/lucene/core/src/test/org/apache/lucene/index/TestMultiDocValues.java b/lucene/core/src/test/org/apache/lucene/index/TestMultiDocValues.java
index 8944dd66b67..0e21308bda4 100644
--- a/lucene/core/src/test/org/apache/lucene/index/TestMultiDocValues.java
+++ b/lucene/core/src/test/org/apache/lucene/index/TestMultiDocValues.java
@@ -121,6 +121,9 @@ public class TestMultiDocValues extends LuceneTestCase {
     int numDocs = atLeast(500);
     for (int i = 0; i < numDocs; i++) {
       ref.copyChars(_TestUtil.randomUnicodeString(random()));
+      if (random().nextInt(7) == 0) {
+        iw.addDocument(new Document());
+      }
       iw.addDocument(doc);
       if (random().nextInt(17) == 0) {
         iw.commit();
@@ -140,7 +143,7 @@ public class TestMultiDocValues extends LuceneTestCase {
     for (int i = 0; i < numDocs; i++) {
       // check ord
       assertEquals(single.getOrd(i), multi.getOrd(i));
-      // check ord value
+      // check value
       single.get(i, expected);
       multi.get(i, actual);
       assertEquals(expected, actual);