diff --git a/lib/Doctrine/ORM/Mapping/ClassMetadataFactory.php b/lib/Doctrine/ORM/Mapping/ClassMetadataFactory.php
index 6a8aed1f42d..98aa7411952 100644
--- a/lib/Doctrine/ORM/Mapping/ClassMetadataFactory.php
+++ b/lib/Doctrine/ORM/Mapping/ClassMetadataFactory.php
@@ -61,9 +61,24 @@ public function setEntityManager(EntityManagerInterface $em): void
         $this->em = $em;
     }
 
+    /**
+     * @param A $maybeOwningSide
+     *
+     * @return (A is ManyToManyAssociationMapping ? ManyToManyOwningSideMapping : (
+     *     A is OneToOneAssociationMapping ? OneToOneOwningSideMapping : (
+     *     A is OneToManyAssociationMapping ? ManyToOneAssociationMapping : (
+     *     A is ManyToOneAssociationMapping ? ManyToOneAssociationMapping : OwningSideMapping
+     * ))))
+     *
+     * @template A of AssociationMapping
+     */
     final public function getOwningSide(AssociationMapping $maybeOwningSide): OwningSideMapping
     {
         if ($maybeOwningSide instanceof OwningSideMapping) {
+            assert($maybeOwningSide instanceof ManyToManyOwningSideMapping ||
+                $maybeOwningSide instanceof OneToOneOwningSideMapping ||
+                $maybeOwningSide instanceof ManyToOneAssociationMapping);
+
             return $maybeOwningSide;
         }
 
@@ -72,7 +87,9 @@ final public function getOwningSide(AssociationMapping $maybeOwningSide): Owning
         $owningSide = $this->getMetadataFor($maybeOwningSide->targetEntity)
             ->associationMappings[$maybeOwningSide->mappedBy];
 
-        assert($owningSide instanceof OwningSideMapping);
+        assert($owningSide instanceof ManyToManyOwningSideMapping ||
+            $owningSide instanceof OneToOneOwningSideMapping ||
+            $owningSide instanceof ManyToOneAssociationMapping);
 
         return $owningSide;
     }
diff --git a/lib/Doctrine/ORM/Persisters/Collection/ManyToManyPersister.php b/lib/Doctrine/ORM/Persisters/Collection/ManyToManyPersister.php
index 9f652292647..64c8accadea 100644
--- a/lib/Doctrine/ORM/Persisters/Collection/ManyToManyPersister.php
+++ b/lib/Doctrine/ORM/Persisters/Collection/ManyToManyPersister.php
@@ -114,8 +114,6 @@ public function count(PersistentCollection $collection): int
         $sourceClass = $this->em->getClassMetadata($mapping->sourceEntity);
         $association = $this->em->getMetadataFactory()->getOwningSide($mapping);
 
-        assert($association->isManyToManyOwningSide());
-
         $joinTableName = $this->quoteStrategy->getJoinTableName($association, $sourceClass, $this->platform);
         $joinColumns   = ! $mapping->isOwningSide()
             ? $association->joinTable['inverseJoinColumns']
@@ -346,9 +344,6 @@ protected function generateFilterConditionSQL(ClassMetadata $targetEntity, strin
     protected function getOnConditionSQL(AssociationMapping $mapping): array
     {
         $association = $this->em->getMetadataFactory()->getOwningSide($mapping);
-
-        assert($association->isManyToManyOwningSide());
-
         $joinColumns = $mapping->isOwningSide()
             ? $association->joinTable['inverseJoinColumns']
             : $association->joinTable['joinColumns'];
@@ -680,7 +675,6 @@ private function getJoinTableRestrictions(
         $params          = [];
         $types           = [];
 
-        assert($mapping->isManyToManyOwningSide());
         foreach ($mapping->joinTableColumns as $joinTableColumn) {
             $whereClauses[] = ($addFilters ? 't.' : '') . $joinTableColumn . ' = ?';
 
diff --git a/lib/Doctrine/ORM/Persisters/Entity/BasicEntityPersister.php b/lib/Doctrine/ORM/Persisters/Entity/BasicEntityPersister.php
index d039f3627a7..0629e409edd 100644
--- a/lib/Doctrine/ORM/Persisters/Entity/BasicEntityPersister.php
+++ b/lib/Doctrine/ORM/Persisters/Entity/BasicEntityPersister.php
@@ -21,6 +21,7 @@
 use Doctrine\ORM\Mapping\ClassMetadata;
 use Doctrine\ORM\Mapping\InverseSideMapping;
 use Doctrine\ORM\Mapping\JoinColumnMapping;
+use Doctrine\ORM\Mapping\ManyToManyAssociationMapping;
 use Doctrine\ORM\Mapping\MappingException;
 use Doctrine\ORM\Mapping\OneToManyAssociationMapping;
 use Doctrine\ORM\Mapping\QuoteStrategy;
@@ -518,9 +519,6 @@ protected function deleteJoinTableRecords(array $identifier, array $types): void
             }
 
             $association = $this->em->getMetadataFactory()->getOwningSide($association);
-
-            assert($association->isManyToManyOwningSide());
-
             $joinColumns = $mapping->isOwningSide()
                 ? $association->joinTable['joinColumns']
                 : $association->joinTable['inverseJoinColumns'];
@@ -902,6 +900,7 @@ public function getManyToManyCollection(
         int|null $offset = null,
         int|null $limit = null,
     ): array {
+        assert($assoc->isManyToMany());
         $this->switchPersisterContext($offset, $limit);
 
         $stmt = $this->getManyToManyStatement($assoc, $sourceEntity, $offset, $limit);
@@ -956,6 +955,7 @@ private function loadCollectionFromStatement(
      */
     public function loadManyToManyCollection(AssociationMapping $assoc, object $sourceEntity, PersistentCollection $collection): array
     {
+        assert($assoc->isManyToMany());
         $stmt = $this->getManyToManyStatement($assoc, $sourceEntity);
 
         return $this->loadCollectionFromStatement($assoc, $stmt, $collection);
@@ -963,7 +963,7 @@ public function loadManyToManyCollection(AssociationMapping $assoc, object $sour
 
     /** @throws MappingException */
     private function getManyToManyStatement(
-        AssociationMapping $assoc,
+        AssociationMapping&ManyToManyAssociationMapping $assoc,
         object $sourceEntity,
         int|null $offset = null,
         int|null $limit = null,
@@ -977,14 +977,10 @@ private function getManyToManyStatement(
         $parameters  = [];
 
         if (! $assoc->isOwningSide()) {
-            assert(isset($assoc->mappedBy));
             $class = $this->em->getClassMetadata($assoc->targetEntity);
         }
 
         $association = $this->em->getMetadataFactory()->getOwningSide($assoc);
-
-        assert($association->isManyToManyOwningSide());
-
         $joinColumns = $assoc->isOwningSide()
             ? $association->joinTable['joinColumns']
             : $association->joinTable['inverseJoinColumns'];
@@ -1331,15 +1327,13 @@ protected function getSelectColumnAssociationSQL(
      * Gets the SQL join fragment used when selecting entities from a
      * many-to-many association.
      */
-    protected function getSelectManyToManyJoinSQL(AssociationMapping $manyToMany): string
+    protected function getSelectManyToManyJoinSQL(AssociationMapping&ManyToManyAssociationMapping $manyToMany): string
     {
         $conditions       = [];
         $association      = $manyToMany;
         $sourceTableAlias = $this->getSQLTableAlias($this->class->name);
 
-        $association = $this->em->getMetadataFactory()->getOwningSide($manyToMany);
-        assert($association->isManyToManyOwningSide());
-
+        $association   = $this->em->getMetadataFactory()->getOwningSide($manyToMany);
         $joinTableName = $this->quoteStrategy->getJoinTableName($association, $this->class, $this->platform);
         $joinColumns   = $manyToMany->isOwningSide()
             ? $association->joinTable['inverseJoinColumns']
@@ -1861,7 +1855,7 @@ private function getTypes(string $field, mixed $value, ClassMetadata $class): ar
                 if ($assoc->isManyToManyOwningSide()) {
                     $columns = $assoc->relationToTargetKeyColumns;
                 } else {
-                    assert($assoc->isToOneOwningSide() || $assoc->isManyToOne());
+                    assert($assoc->isToOneOwningSide());
                     $columns = $assoc->sourceToTargetKeyColumns;
                 }
 
diff --git a/phpstan.neon b/phpstan.neon
index 1774b1f74d8..d63c4b8b0fc 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -45,3 +45,9 @@ parameters:
                 - lib/Doctrine/ORM/Persisters/Entity/JoinedSubclassPersister.php
                 - lib/Doctrine/ORM/Query/SqlWalker.php
                 - lib/Doctrine/ORM/Tools/SchemaValidator.php
+
+        -
+            message: '#^.*Doctrine\\ORM\\Mapping\\AssociationMapping&Doctrine\\ORM\\Mapping\\ManyToManyAssociationMapping, Doctrine\\ORM\\Mapping\\AssociationMapping given\.#'
+            paths:
+                - lib/Doctrine/ORM/Persisters/Entity/BasicEntityPersister.php
+                - lib/Doctrine/ORM/Persisters/Entity/JoinedSubclassPersister.php
diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index 2a010d89f72..78135a9cbb4 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -407,6 +407,11 @@
       <code><![CDATA[$parent->generatorType]]></code>
       <code><![CDATA[$parent->idGenerator]]></code>
     </RedundantCondition>
+    <RedundantConditionGivenDocblockType>
+      <code>assert($owningSide instanceof ManyToManyOwningSideMapping ||
+            $owningSide instanceof OneToOneOwningSideMapping ||
+            $owningSide instanceof ManyToOneAssociationMapping)</code>
+    </RedundantConditionGivenDocblockType>
   </file>
   <file src="lib/Doctrine/ORM/Mapping/DefaultEntityListenerResolver.php">
     <InvalidStringClass>