diff --git a/core/lib/Drupal/Core/Logger/LoggerBase.php b/core/lib/Drupal/Core/Logger/LoggerBase.php
index 6bcef8c..2a81271 100644
--- a/core/lib/Drupal/Core/Logger/LoggerBase.php
+++ b/core/lib/Drupal/Core/Logger/LoggerBase.php
@@ -37,7 +37,7 @@ protected function parseMessagePlaceholders(&$message, array &$context) {
     if (($start = strpos($message, '{')) !== FALSE && strpos($message, '}') > $start) {
       $has_ps3 = TRUE;
       // Replace PS3 messages containing placeholders.
-      $message = preg_replace('/\{(.*)\}/', '@$1', $message);
+      $message = preg_replace('/\{(.*)\}/U', '@$1', $message);
     }
     foreach ($context as $key => $variable) {
       // PSR3 style placeholders.
@@ -49,7 +49,7 @@ protected function parseMessagePlaceholders(&$message, array &$context) {
           $key = '@' . $key;
         }
       }
-      if (strpos($key, '@') === 0 || strpos($key, '%') === 0 || strpos($key, '!') === 0) {
+      if (!empty($key) && ($key[0] === '@' || $key[0] === '%' || $key[0] === '!')) {
         // The key is now in \Drupal\Component\Utility\String::format() style.
         $variables[$key] = $variable;
       }
diff --git a/core/tests/Drupal/Tests/Core/Logger/LoggerBaseTest.php b/core/tests/Drupal/Tests/Core/Logger/LoggerBaseTest.php
index 54cd479..5a2b79e 100644
--- a/core/tests/Drupal/Tests/Core/Logger/LoggerBaseTest.php
+++ b/core/tests/Drupal/Tests/Core/Logger/LoggerBaseTest.php
@@ -80,6 +80,11 @@ public function providerTestParseMessagePlaceholders() {
         array('message' => 'User W-\\};~{&! created @', 'context' => array('' => '')),
         array('message' => 'User W-\\};~{&! created @', 'context' => array()),
       ),
+      // Messsage with double PSR3 style messages.
+      array(
+        array('message' => 'Test {with} two {encapsuled} strings', 'context' => array('with' => 'together', 'encapsuled' => 'awesome')),
+        array('message' => 'Test @with two @encapsuled strings', 'context' => array('@with' => 'together', '@encapsuled' => 'awesome')),
+      ),
     );
   }