diff --git a/src/Schema/Elements/Type.php b/src/Schema/Elements/Type.php
index adf0815..ad96f20 100644
--- a/src/Schema/Elements/Type.php
+++ b/src/Schema/Elements/Type.php
@@ -142,6 +142,12 @@ public function merge($value, $base)
 
 	public function complete($value, Context $context)
 	{
+		$merge = $this->merge;
+		if (is_array($value) && isset($value[Helpers::PREVENT_MERGING])) {
+			unset($value[Helpers::PREVENT_MERGING]);
+			$merge = false;
+		}
+
 		if ($value === null && is_array($this->default)) {
 			$value = []; // is unable to distinguish null from array in NEON
 		}
@@ -180,7 +186,7 @@ public function complete($value, Context $context)
 			}
 		}
 
-		if ($this->merge) {
+		if ($merge) {
 			$value = Helpers::merge($value, $this->default);
 		}
 		return $this->doFinalize($value, $context);
diff --git a/tests/Schema/Expect.array.phpt b/tests/Schema/Expect.array.phpt
index 9008a39..4d70c45 100644
--- a/tests/Schema/Expect.array.phpt
+++ b/tests/Schema/Expect.array.phpt
@@ -3,6 +3,7 @@
 declare(strict_types=1);
 
 use Nette\Schema\Expect;
+use Nette\Schema\Helpers;
 use Nette\Schema\Processor;
 use Tester\Assert;
 
@@ -90,7 +91,41 @@ test('merging', function () {
 		(new Processor)->process($schema, [
 			'key1' => 'newval',
 			'key3' => 'newval',
-			'newval3', 'arr' => ['newitem'],
+			'newval3',
+			'arr' => ['newitem'],
+		])
+	);
+
+	Assert::same(
+		[
+			'key1' => 'newval',
+			'key3' => 'newval',
+			'newval3',
+			'arr' => ['newitem'],
+		],
+		(new Processor)->process($schema, [
+			Helpers::PREVENT_MERGING => true,
+			'key1' => 'newval',
+			'key3' => 'newval',
+			'newval3',
+			'arr' => ['newitem'],
+		])
+	);
+
+	Assert::same(
+		[
+			'key1' => 'newval',
+			'key2' => 'val2',
+			'val3',
+			'arr' => ['newitem'],
+			'key3' => 'newval',
+			'newval3',
+		],
+		(new Processor)->process($schema, [
+			'key1' => 'newval',
+			'key3' => 'newval',
+			'newval3',
+			'arr' => [Helpers::PREVENT_MERGING => true, 'newitem'],
 		])
 	);
 });