diff --git a/core/lib/Drupal/Core/Database/Driver/pgsql/Schema.php b/core/lib/Drupal/Core/Database/Driver/pgsql/Schema.php
index 2190ee5..a57bce3 100644
--- a/core/lib/Drupal/Core/Database/Driver/pgsql/Schema.php
+++ b/core/lib/Drupal/Core/Database/Driver/pgsql/Schema.php
@@ -216,7 +216,11 @@ protected function createTableSql($name, $table) {
 
     if (isset($table['indexes']) && is_array($table['indexes'])) {
       foreach ($table['indexes'] as $key_name => $key) {
-        $statements[] = $this->_createIndexSql($name, $key_name, $key);
+        // Prevent from creating an index twice. This could happen as PostgreSQL
+        // indexes are global.
+        if (!$this->indexExists($name, $key_name)) {
+          $statements[] = $this->_createIndexSql($name, $key_name, $key);
+        }
       }
     }