diff --git a/Source/Engine/Core/Collections/HashSet.h b/Source/Engine/Core/Collections/HashSet.h
index ab2601525..6751be0dc 100644
--- a/Source/Engine/Core/Collections/HashSet.h
+++ b/Source/Engine/Core/Collections/HashSet.h
@@ -408,7 +408,7 @@ public:
     template<typename ItemType>
     bool Add(const ItemType& item)
     {
-        Bucket* bucket = Base::OnAdd(item, false);
+        Bucket* bucket = Base::OnAdd(item, false, true);
         if (bucket)
             bucket->Occupy(item);
         return bucket != nullptr;
@@ -421,7 +421,7 @@ public:
     /// <returns>True if element has been added to the collection, otherwise false if the element is already present.</returns>
     bool Add(T&& item)
     {
-        Bucket* bucket = Base::OnAdd(item, false);
+        Bucket* bucket = Base::OnAdd(item, false, true);
         if (bucket)
             bucket->Occupy(MoveTemp(item));
         return bucket != nullptr;
diff --git a/Source/Engine/Core/Collections/HashSetBase.h b/Source/Engine/Core/Collections/HashSetBase.h
index 200e26b7b..488613d2b 100644
--- a/Source/Engine/Core/Collections/HashSetBase.h
+++ b/Source/Engine/Core/Collections/HashSetBase.h
@@ -359,7 +359,7 @@ protected:
     }
 
     template<typename KeyComparableType>
-    BucketType* OnAdd(const KeyComparableType& key, bool checkUnique = true)
+    BucketType* OnAdd(const KeyComparableType& key, bool checkUnique = true, bool nullIfNonUnique = false)
     {
         // Check if need to rehash elements (prevent many deleted elements that use too much of capacity)
         if (_deletedCount * HASH_SET_DEFAULT_SLACK_SCALE > _size)
@@ -380,6 +380,8 @@ protected:
                 Platform::CheckFailed("That key has been already added to the collection.", __FILE__, __LINE__);
                 return nullptr;
             }
+            if (nullIfNonUnique)
+                return nullptr;
             return &_allocation.Get()[pos.ObjectIndex];
         }