diff --git a/src/Illuminate/Routing/RoutingServiceProvider.php b/src/Illuminate/Routing/RoutingServiceProvider.php
index 0221839fc8df..a2ca675da4e2 100755
--- a/src/Illuminate/Routing/RoutingServiceProvider.php
+++ b/src/Illuminate/Routing/RoutingServiceProvider.php
@@ -139,7 +139,7 @@ protected function registerPsrRequest()
 
                 return with((new PsrHttpFactory($psr17Factory, $psr17Factory, $psr17Factory, $psr17Factory))
                     ->createRequest($illuminateRequest = $app->make('request')), fn ($request) => $request->withParsedBody(
-                        array_merge($request->getParsedBody(), $illuminateRequest->getPayload()->all())
+                        array_merge($request->getParsedBody() ?? [], $illuminateRequest->getPayload()->all())
                     ));
             }
 
diff --git a/tests/Integration/Foundation/RoutingServiceProviderTest.php b/tests/Integration/Foundation/RoutingServiceProviderTest.php
index 859b348eb774..4753f03eda02 100644
--- a/tests/Integration/Foundation/RoutingServiceProviderTest.php
+++ b/tests/Integration/Foundation/RoutingServiceProviderTest.php
@@ -26,6 +26,42 @@ public function testItIncludesMergedDataInServerRequestInterfaceInstancesUsingGe
         ]);
     }
 
+    public function testItWorksNormallyWithoutMergeDataMiddlewareWithEmptyRequests()
+    {
+        Route::get('test-route', function (ServerRequestInterface $request) {
+            return $request->getParsedBody();
+        });
+
+        $response = $this->withoutExceptionHandling()->get('test-route', [
+            'content-type' => 'application/json',
+        ]);
+
+        $response->assertOk();
+        $response->assertExactJson([]);
+    }
+
+    public function testItIncludesMergedDataInServerRequestInterfaceInstancesUsingGetJsonRequestsWithContentTypeHeader()
+    {
+        Route::get('test-route', function (ServerRequestInterface $request) {
+            return $request->getParsedBody();
+        })->middleware(MergeDataMiddleware::class);
+
+        $response = $this->getJson('test-route?'.http_build_query([
+            'sent' => 'sent-data',
+            'overridden' => 'overriden-sent-data',
+        ]), [
+            'content-type' => 'application/json',
+        ]);
+
+        $response->assertOk();
+        $response->assertExactJson([
+            'json-data' => 'json-data',
+            'merged' => 'replaced-merged-data',
+            'overridden' => 'overriden-merged-data',
+            'request-data' => 'request-data',
+        ]);
+    }
+
     public function testItIncludesMergedDataInServerRequestInterfaceInstancesUsingGetJsonRequests()
     {
         Route::get('test-route', function (ServerRequestInterface $request) {