diff --git a/src/Rector/Dynamic/NamespaceReplacerRector.php b/src/Rector/Dynamic/NamespaceReplacerRector.php
index 09dc7d437d4..a6c47d17046 100644
--- a/src/Rector/Dynamic/NamespaceReplacerRector.php
+++ b/src/Rector/Dynamic/NamespaceReplacerRector.php
@@ -4,6 +4,7 @@ namespace Rector\Rector\Dynamic;
 
 use Nette\Utils\Strings;
 use PhpParser\Node;
+use PhpParser\Node\Expr\New_;
 use PhpParser\Node\Name;
 use PhpParser\Node\Name\FullyQualified;
 use PhpParser\Node\Stmt\Namespace_;
@@ -33,8 +34,11 @@ final class NamespaceReplacerRector extends AbstractRector
         }
 
         $name = $this->resolveNameFromNode($node);
+        if (! $this->isNamespaceToChange($name)) {
+            return false;
+        }
 
-        return $this->isNamespaceToChange($name);
+        return ! $this->isClassFullyQualifiedName($node);
     }
 
     public function refactor(Node $node): ?Node
@@ -122,4 +126,29 @@ final class NamespaceReplacerRector extends AbstractRector
 
         return false;
     }
+
+    /**
+     * Checks for "new \ClassNoNamespace;"
+     * This should be skipped, not a namespace.
+     */
+    private function isClassFullyQualifiedName(Node $node): bool
+    {
+        $parentNode = $node->getAttribute(Attribute::PARENT_NODE);
+        if ($parentNode === null) {
+            return false;
+        }
+
+        if (! $parentNode instanceof New_) {
+            return false;
+        }
+
+        $newClassName = $parentNode->class->toString();
+        foreach ($this->oldToNewNamespaces as $oldNamespace => $newNamespace) {
+            if ($newClassName === $oldNamespace) {
+                return true;
+            }
+        }
+
+        return false;
+    }
 }
diff --git a/tests/Rector/Dynamic/NamespaceReplacerRector/correct/correct.php.inc b/tests/Rector/Dynamic/NamespaceReplacerRector/correct/correct.php.inc
index b7ce82561b0..bfdc67c138c 100644
--- a/tests/Rector/Dynamic/NamespaceReplacerRector/correct/correct.php.inc
+++ b/tests/Rector/Dynamic/NamespaceReplacerRector/correct/correct.php.inc
@@ -9,6 +9,8 @@ class SomeClass
 {
     public function someClass()
     {
+        $keepThis = new \OldNamespace;
+
         return new \NewNamespace\SomeClass;
     }
 }
diff --git a/tests/Rector/Dynamic/NamespaceReplacerRector/wrong/wrong.php.inc b/tests/Rector/Dynamic/NamespaceReplacerRector/wrong/wrong.php.inc
index a7057a8f807..cb27b6bb48c 100644
--- a/tests/Rector/Dynamic/NamespaceReplacerRector/wrong/wrong.php.inc
+++ b/tests/Rector/Dynamic/NamespaceReplacerRector/wrong/wrong.php.inc
@@ -9,6 +9,8 @@ class SomeClass
 {
     public function someClass()
     {
+        $keepThis = new \OldNamespace;
+
         return new \OldNamespace\SomeClass;
     }
 }