diff --git a/src/mlpack/core/metrics/ip_metric_impl.hpp b/src/mlpack/core/metrics/ip_metric_impl.hpp
index d39026593..5155eb380 100644
--- a/src/mlpack/core/metrics/ip_metric_impl.hpp
+++ b/src/mlpack/core/metrics/ip_metric_impl.hpp
@@ -65,6 +65,10 @@ template<typename Archive>
 void IPMetric<KernelType>::serialize(Archive& ar,
                                      const unsigned int /* version */)
 {
+  // Delete an existing kernel.
+  if (kernelOwner)
+    delete kernel;
+
   // If we're loading, we need to allocate space for the kernel, and we will own
   // the kernel.
   if (Archive::is_loading::value)