diff --git a/src/Symfony/Component/ObjectMapper/ObjectMapper.php b/src/Symfony/Component/ObjectMapper/ObjectMapper.php
index 87f0a821a71d..64840948aa45 100644
--- a/src/Symfony/Component/ObjectMapper/ObjectMapper.php
+++ b/src/Symfony/Component/ObjectMapper/ObjectMapper.php
@@ -144,6 +144,11 @@ public function map(object $source, object|string|null $target = null): object
             }
 
             if (!$mappings && $targetRefl->hasProperty($propertyName)) {
+                $sourceProperty = $refl->getProperty($propertyName);
+                if ($refl->isInstance($source) && !$sourceProperty->isInitialized($source)) {
+                    continue;
+                }
+
                 $value = $this->getSourceValue($source, $mappedTarget, $this->getRawValue($source, $propertyName), $this->objectMap);
                 $this->storeValue($propertyName, $mapToProperties, $ctorArguments, $value);
             }
diff --git a/src/Symfony/Component/ObjectMapper/Tests/Fixtures/PartialInput/FinalInput.php b/src/Symfony/Component/ObjectMapper/Tests/Fixtures/PartialInput/FinalInput.php
new file mode 100644
index 000000000000..2aeab4c5bcab
--- /dev/null
+++ b/src/Symfony/Component/ObjectMapper/Tests/Fixtures/PartialInput/FinalInput.php
@@ -0,0 +1,11 @@
+<?php
+
+namespace Symfony\Component\ObjectMapper\Tests\Fixtures\PartialInput;
+
+class FinalInput
+{
+    public string $uuid;
+    public string $name;
+    public ?string $email = null;
+    public ?string $website = null;
+}
diff --git a/src/Symfony/Component/ObjectMapper/Tests/Fixtures/PartialInput/PartialInput.php b/src/Symfony/Component/ObjectMapper/Tests/Fixtures/PartialInput/PartialInput.php
new file mode 100644
index 000000000000..eca757c9bad2
--- /dev/null
+++ b/src/Symfony/Component/ObjectMapper/Tests/Fixtures/PartialInput/PartialInput.php
@@ -0,0 +1,14 @@
+<?php
+
+namespace Symfony\Component\ObjectMapper\Tests\Fixtures\PartialInput;
+
+use Symfony\Component\ObjectMapper\Attribute\Map;
+
+#[Map(target: FinalInput::class)]
+class PartialInput
+{
+    public string $uuid;
+    public string $name;
+    public ?string $email;
+    public ?string $website;
+}
diff --git a/src/Symfony/Component/ObjectMapper/Tests/ObjectMapperTest.php b/src/Symfony/Component/ObjectMapper/Tests/ObjectMapperTest.php
index 8cb3b82c2baa..85b09d1ad99c 100644
--- a/src/Symfony/Component/ObjectMapper/Tests/ObjectMapperTest.php
+++ b/src/Symfony/Component/ObjectMapper/Tests/ObjectMapperTest.php
@@ -54,6 +54,8 @@
 use Symfony\Component\ObjectMapper\Tests\Fixtures\MultipleTargets\A as MultipleTargetsA;
 use Symfony\Component\ObjectMapper\Tests\Fixtures\MultipleTargets\C as MultipleTargetsC;
 use Symfony\Component\ObjectMapper\Tests\Fixtures\MyProxy;
+use Symfony\Component\ObjectMapper\Tests\Fixtures\PartialInput\FinalInput;
+use Symfony\Component\ObjectMapper\Tests\Fixtures\PartialInput\PartialInput;
 use Symfony\Component\ObjectMapper\Tests\Fixtures\PromotedConstructor\Source as PromotedConstructorSource;
 use Symfony\Component\ObjectMapper\Tests\Fixtures\PromotedConstructor\Target as PromotedConstructorTarget;
 use Symfony\Component\ObjectMapper\Tests\Fixtures\Recursion\AB;
@@ -402,4 +404,47 @@ public function testMapInitializesNativePhp84LazyObject()
         $this->assertSame('test', $d->name);
         $this->assertTrue($initialized);
     }
+
+    /**
+     * @dataProvider validPartialInputProvider
+     */
+    public function testMapPartially(PartialInput $actual, FinalInput $expected)
+    {
+        $mapper = new ObjectMapper();
+        $this->assertEquals($expected, $mapper->map($actual));
+    }
+
+    public static function validPartialInputProvider(): iterable
+    {
+        $p = new PartialInput();
+        $p->uuid = '6a9eb6dd-c4dc-4746-bb99-f6bad716acb2';
+        $p->website = 'https://updated.website.com';
+
+        $f = new FinalInput();
+        $f->uuid = $p->uuid;
+        $f->website = $p->website;
+
+        yield [$p, $f];
+
+        $p = new PartialInput();
+        $p->uuid = '6a9eb6dd-c4dc-4746-bb99-f6bad716acb2';
+        $p->website = null;
+
+        $f = new FinalInput();
+        $f->uuid = $p->uuid;
+
+        yield [$p, $f];
+
+        $p = new PartialInput();
+        $p->uuid = '6a9eb6dd-c4dc-4746-bb99-f6bad716acb2';
+        $p->website = 'https://updated.website.com';
+        $p->email = 'updated@email.com';
+
+        $f = new FinalInput();
+        $f->uuid = $p->uuid;
+        $f->website = $p->website;
+        $f->email = $p->email;
+
+        yield [$p, $f];
+    }
 }

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