diff --git a/src/Concerns/Testable.php b/src/Concerns/Testable.php
index e192c8fa..67a16b2c 100644
--- a/src/Concerns/Testable.php
+++ b/src/Concerns/Testable.php
@@ -360,7 +360,7 @@ trait Testable
                 }
 
                 $parameterType = is_string($argumentIndex)
-                    ? ($testParameterTypesByName[$argumentIndex] ?? 'mixed')
+                    ? $testParameterTypesByName[$argumentIndex]
                     : $testParameterTypes[$argumentIndex];
 
                 if (in_array($parameterType, [Closure::class, 'callable', 'mixed'])) {
diff --git a/tests/Features/DatasetsTests.php b/tests/Features/DatasetsTests.php
index b5607106..99682015 100644
--- a/tests/Features/DatasetsTests.php
+++ b/tests/Features/DatasetsTests.php
@@ -533,3 +533,12 @@ test('named parameters work with bound closure returning associative array', fun
         return ['name' => $this->foo, 'email' => 'test@example.com'];
     },
 ]);
+
+test('dataset items can mix named and sequential styles', function (string $name, string $email) {
+    expect($name)->toBeString();
+    expect($email)->toContain('@');
+})->with([
+    ['name' => 'Taylor', 'email' => 'taylor@laravel.com'],
+    ['James', 'james@laravel.com'],
+    ['James', 'email' => 'james@laravel.com'],
+]);