diff --git a/spine-unity/Assets/Spine/Runtime/spine-unity/Components/RootMotion/SkeletonRootMotionBase.cs b/spine-unity/Assets/Spine/Runtime/spine-unity/Components/RootMotion/SkeletonRootMotionBase.cs
index 24b7e5955..248aa1ccf 100644
--- a/spine-unity/Assets/Spine/Runtime/spine-unity/Components/RootMotion/SkeletonRootMotionBase.cs
+++ b/spine-unity/Assets/Spine/Runtime/spine-unity/Components/RootMotion/SkeletonRootMotionBase.cs
@@ -443,7 +443,7 @@ namespace Spine.Unity {
 		int GetConstraintLastPosIndex (int constraintIndex) {
 			var constraints = skeletonComponent.Skeleton.TransformConstraints;
 			TransformConstraint targetConstraint = constraints.Items[constraintIndex];
-			return constraints.FindIndex(constraint => constraint == targetConstraint);
+			return transformConstraintIndices.FindIndex(addedIndex => addedIndex == constraintIndex);
 		}
 
 		void FindTransformConstraintsAffectingBone () {