diff --git a/internal/clientutil/clientutil.go b/internal/clientutil/clientutil.go
index 04cc3678..4b9ec6fe 100644
--- a/internal/clientutil/clientutil.go
+++ b/internal/clientutil/clientutil.go
@@ -1,5 +1,7 @@
 // SPDX-FileCopyrightText: 2025 SAP SE or an SAP affiliate company and IronCore contributors
 // SPDX-License-Identifier: Apache-2.0
+
+// Package clientutil provides a client wrapper for the controller-runtime client with convenience functions.
 package clientutil
 
 import (
@@ -7,6 +9,7 @@ import (
 	"crypto/tls"
 	"errors"
 	"fmt"
+	"slices"
 
 	corev1 "k8s.io/api/core/v1"
 	"sigs.k8s.io/controller-runtime/pkg/client"
@@ -50,7 +53,9 @@ func (c *Client) Get(ctx context.Context, key client.ObjectKey, obj client.Objec
 // returned from the Server. It will automatically restrict the request to the
 // namespace that is set in the Client.
 func (c *Client) List(ctx context.Context, list client.ObjectList, opts ...client.ListOption) error {
-	opts = append(opts, client.InNamespace(c.DefaultNamespace))
+	if slices.ContainsFunc(opts, func(opt client.ListOption) bool { _, ok := opt.(client.InNamespace); return ok }) {
+		opts = append(opts, client.InNamespace(c.DefaultNamespace))
+	}
 	return c.r.List(ctx, list, opts...)
 }
 
diff --git a/internal/controller/core/device_controller.go b/internal/controller/core/device_controller.go
index 2a5f24e0..ae07e1d1 100644
--- a/internal/controller/core/device_controller.go
+++ b/internal/controller/core/device_controller.go
@@ -241,10 +241,8 @@ func (r *DeviceReconciler) reconcile(ctx context.Context, device *v1alpha1.Devic
 			return fmt.Errorf("failed to list device ports: %w", err)
 		}
 
-		c := clientutil.NewClient(r.Client, device.Namespace)
-
 		interfaces := new(v1alpha1.InterfaceList)
-		if err := c.List(ctx, interfaces, client.InNamespace(device.Namespace), client.MatchingLabels{v1alpha1.DeviceLabel: device.Name}); err != nil {
+		if err := r.List(ctx, interfaces, client.InNamespace(device.Namespace), client.MatchingLabels{v1alpha1.DeviceLabel: device.Name}); err != nil {
 			return fmt.Errorf("failed to list interface resources for device: %w", err)
 		}
 
diff --git a/internal/controller/core/isis_controller.go b/internal/controller/core/isis_controller.go
index d07d588f..d49f1a35 100644
--- a/internal/controller/core/isis_controller.go
+++ b/internal/controller/core/isis_controller.go
@@ -22,7 +22,6 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/predicate"
 
 	"github.com/ironcore-dev/network-operator/api/core/v1alpha1"
-	"github.com/ironcore-dev/network-operator/internal/clientutil"
 	"github.com/ironcore-dev/network-operator/internal/conditions"
 	"github.com/ironcore-dev/network-operator/internal/deviceutil"
 	"github.com/ironcore-dev/network-operator/internal/provider"
@@ -223,12 +222,10 @@ func (r *ISISReconciler) reconcile(ctx context.Context, s *isisScope) (_ ctrl.Re
 		}
 	}
 
-	c := clientutil.NewClient(r, s.ISIS.Namespace)
-
 	var interfaces []provider.ISISInterface
 	for _, iface := range s.ISIS.Spec.Interfaces {
 		res := new(v1alpha1.Interface)
-		if err := c.Get(ctx, client.ObjectKey{Name: iface.Ref.Name}, res); err != nil {
+		if err := r.Get(ctx, client.ObjectKey{Name: iface.Ref.Name, Namespace: s.ISIS.Namespace}, res); err != nil {
 			return ctrl.Result{}, err
 		}