diff --git a/Classes/EventListener/EnhancedRouting/CachedPathVariableModifier.php b/Classes/EventListener/EnhancedRouting/CachedPathVariableModifier.php
index cb8ef5c981..afc472bb0e 100644
--- a/Classes/EventListener/EnhancedRouting/CachedPathVariableModifier.php
+++ b/Classes/EventListener/EnhancedRouting/CachedPathVariableModifier.php
@@ -52,7 +52,7 @@ public function __invoke(BeforeProcessCachedVariablesEvent $event): void
 
         $this->routingService = GeneralUtility::makeInstance(
             RoutingService::class,
-            $enhancerConfiguration['solr'],
+            $enhancerConfiguration['solr'] ?? [],
             (string)$enhancerConfiguration['extensionKey']
         );
 
diff --git a/Classes/EventListener/EnhancedRouting/PostEnhancedUriProcessor.php b/Classes/EventListener/EnhancedRouting/PostEnhancedUriProcessor.php
index 28eaadfca7..3baf57f8a5 100644
--- a/Classes/EventListener/EnhancedRouting/PostEnhancedUriProcessor.php
+++ b/Classes/EventListener/EnhancedRouting/PostEnhancedUriProcessor.php
@@ -38,7 +38,7 @@ public function __invoke(PostProcessUriEvent $event): void
         /* @var RoutingService $routingService */
         $routingService = GeneralUtility::makeInstance(
             RoutingService::class,
-            $configuration['solr'],
+            $configuration['solr'] ?? [],
             (string)$configuration['extensionKey']
         );
 
diff --git a/Classes/Middleware/SolrRoutingMiddleware.php b/Classes/Middleware/SolrRoutingMiddleware.php
index 37625d4971..edb5fe4477 100644
--- a/Classes/Middleware/SolrRoutingMiddleware.php
+++ b/Classes/Middleware/SolrRoutingMiddleware.php
@@ -101,7 +101,7 @@ public function injectRoutingService(RoutingService $routingService)
      */
     public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
     {
-        if (!$request->hasHeader(PageIndexerRequest::SOLR_INDEX_HEADER)) {
+        if ($request->hasHeader(PageIndexerRequest::SOLR_INDEX_HEADER)) {
             return $handler->handle($request);
         }
 
@@ -145,7 +145,7 @@ public function process(ServerRequestInterface $request, RequestHandlerInterface
         /*
          * Take slug path segments and argument from incoming URI
          */
-        [$slug, $parameters] = $this->extractParametersFromUriPath(
+        [, $parameters] = $this->extractParametersFromUriPath(
             $request->getUri(),
             $enhancerConfiguration['routePath'],
             $page['slug'] ?? ''
@@ -195,7 +195,7 @@ public function process(ServerRequestInterface $request, RequestHandlerInterface
      */
     protected function configure(array $enhancerConfiguration): void
     {
-        $this->settings = $enhancerConfiguration['solr'];
+        $this->settings = $enhancerConfiguration['solr'] ?? [];
         $this->namespace = $enhancerConfiguration['extensionKey'] ?? $this->namespace;
         $this->routingService = null;
     }
@@ -320,45 +320,42 @@ protected function retrievePageInformation(UriInterface $uri, Site $site): array
                 $path,
                 $this->language
             );
+
             if (empty($items)) {
-                $this->logger
-                    ->/** @scrutinizer ignore-call */
-                    error(
-                        vsprintf(
-                            'Could not determine page for slug "%1$s" and language "%2$s". Given path "%3$s"',
-                            [
-                                $path,
-                                $this->language->getTwoLetterIsoCode(),
-                                $uri->getPath(),
-                            ]
-                        )
-                    );
+                if (empty($path)) {
+                    $message = 'Could not resolve page by path "%3$s" and language "%2$s".';
+                } else {
+                    $message = 'Could not determine page for slug "%1$s" and language "%2$s". Given path "%3$s"';
+                }
+
+                $this->logger->error(
+                    sprintf(
+                        $message,
+                        $path,
+                        $this->language->getTwoLetterIsoCode(),
+                        $uri->getPath()
+                    )
+                );
                 $scan = false;
-            } elseif (empty($path)) {
-                $this->logger
-                    ->/** @scrutinizer ignore-call */
-                    error(
-                        vsprintf(
-                            'Could not resolve page by path "%1$s" and language "%2$s".',
-                            [
-                                $uri->getPath(),
-                                $this->language->getTwoLetterIsoCode(),
-                            ]
-                        )
-                    );
+            } elseif (empty($path) && count($items) === 1) {
+                $page = $items[0];
+                $this->logger->info(
+                    sprintf(
+                        'Path "%1$s" -> slug "%2$s"',
+                        $uri->getPath(),
+                        $page['slug']
+                    )
+                );
                 $scan = false;
             } else {
                 foreach ($items as $item) {
-                    $this->logger
-                        ->info(
-                            vsprintf(
-                                'Path "%1$s" -> slug "%2$s"',
-                                [
-                                    $path,
-                                    $item['slug'],
-                                ]
-                            )
-                        );
+                    $this->logger->info(
+                        sprintf(
+                            'Path "%1$s" -> slug "%2$s"',
+                            $path,
+                            $item['slug']
+                        )
+                    );
 
                     if ($item['slug'] === $path) {
                         $page = $item;
diff --git a/Classes/Routing/Enhancer/SolrFacetMaskAndCombineEnhancer.php b/Classes/Routing/Enhancer/SolrFacetMaskAndCombineEnhancer.php
index d5111f3480..1a0ae38ed5 100644
--- a/Classes/Routing/Enhancer/SolrFacetMaskAndCombineEnhancer.php
+++ b/Classes/Routing/Enhancer/SolrFacetMaskAndCombineEnhancer.php
@@ -326,7 +326,7 @@ protected function getRoutingService(): RoutingService
     {
         return GeneralUtility::makeInstance(
             RoutingService::class,
-            $this->configuration['solr'],
+            $this->configuration['solr'] ?? [],
             (string)$this->configuration['extensionKey']
         )->withPathArguments($this->configuration['_arguments']);
     }
diff --git a/Tests/Unit/Middleware/SolrRoutingMiddlewareTest.php b/Tests/Unit/Middleware/SolrRoutingMiddlewareTest.php
index 13d28f0ccf..386d2e5fab 100644
--- a/Tests/Unit/Middleware/SolrRoutingMiddlewareTest.php
+++ b/Tests/Unit/Middleware/SolrRoutingMiddlewareTest.php
@@ -87,14 +87,11 @@ public function getRequest(): ServerRequestInterface
      * @test
      * @covers \ApacheSolrForTypo3\Solr\Middleware\SolrRoutingMiddleware::process
      */
-    public function missingEnhancerHasNoEffectTest()
+    public function missingEnhancerHasNoEffectTest(): void
     {
         $serverRequest = new ServerRequest(
             'GET',
             'https://domain.example/facet/bar,buz,foo',
-            [
-                PageIndexerRequest::SOLR_INDEX_HEADER => '1',
-            ]
         );
         $siteMatcherMock = $this->getMockBuilder(SiteMatcher::class)
             ->disableOriginalConstructor()
@@ -144,4 +141,28 @@ public function missingEnhancerHasNoEffectTest()
             $uri->getPath()
         );
     }
+
+    /**
+     * @test
+     * @covers \ApacheSolrForTypo3\Solr\Middleware\SolrRoutingMiddleware::process
+     */
+    public function enhancerInactiveDuringIndexingTest(): void
+    {
+        $serverRequest = new ServerRequest(
+            'GET',
+            'https://domain.example/',
+            [
+                PageIndexerRequest::SOLR_INDEX_HEADER => '1',
+            ]
+        );
+
+        $this->routingServiceMock->expects(self::never())->method('getSiteMatcher');
+        $solrRoutingMiddleware = new SolrRoutingMiddleware();
+        $solrRoutingMiddleware->setLogger(new NullLogger());
+        $solrRoutingMiddleware->injectRoutingService($this->routingServiceMock);
+        $solrRoutingMiddleware->process(
+            $serverRequest,
+            $this->responseOutputHandler
+        );
+    }
 }