diff --git a/plugins/org.eclipse.m2m.qvt.oml/src/org/eclipse/m2m/internal/qvt/oml/evaluator/QvtOperationalEvaluationVisitorImpl.java b/plugins/org.eclipse.m2m.qvt.oml/src/org/eclipse/m2m/internal/qvt/oml/evaluator/QvtOperationalEvaluationVisitorImpl.java
index 7492fcb..f7d6be3 100644
--- a/plugins/org.eclipse.m2m.qvt.oml/src/org/eclipse/m2m/internal/qvt/oml/evaluator/QvtOperationalEvaluationVisitorImpl.java
+++ b/plugins/org.eclipse.m2m.qvt.oml/src/org/eclipse/m2m/internal/qvt/oml/evaluator/QvtOperationalEvaluationVisitorImpl.java
@@ -1984,7 +1984,7 @@
 		
     	for (EStructuralFeature tupleProp : tupleType.oclProperties()) {
 			Object propVal = evalEnv.getValueOf(tupleProp.getName());
-			if(propVal == null) {
+			if(propVal == null && isMapping) {
 				ModelParameter extent = null;
 				for (VarParameter resultParam : resultParams) {
 					if(tupleProp.getName().equals(resultParam.getName())) {
@@ -1994,9 +1994,7 @@
 					}
 				}
 				
-				if(isMapping) {
-					propVal = createInstance(tupleProp.getEType(), extent);
-				}
+				propVal = createInstance(tupleProp.getEType(), extent);
 			}
 			values.put(tupleProp, propVal);
 			evalEnv.replace(tupleProp.getName(), propVal, tupleProp.getEType());