diff --git a/dspace-api/src/main/java/org/dspace/content/DSpaceObjectServiceImpl.java b/dspace-api/src/main/java/org/dspace/content/DSpaceObjectServiceImpl.java
index 2f906c2b22..d9020e6141 100644
--- a/dspace-api/src/main/java/org/dspace/content/DSpaceObjectServiceImpl.java
+++ b/dspace-api/src/main/java/org/dspace/content/DSpaceObjectServiceImpl.java
@@ -625,7 +625,9 @@ public abstract class DSpaceObjectServiceImpl<T extends DSpaceObject> implements
                 public int compare(MetadataValue o1, MetadataValue o2) {
                     int compare = o1.getPlace() - o2.getPlace();
                     if (compare == 0) {
-                        if (o1 instanceof RelationshipMetadataValue) {
+                        if (o1 instanceof RelationshipMetadataValue && o2 instanceof RelationshipMetadataValue) {
+                            return compare;
+                        } else if (o1 instanceof RelationshipMetadataValue) {
                             return 1;
                         } else if (o2 instanceof RelationshipMetadataValue) {
                             return -1;