diff --git a/Solr_Base_Query.php b/Solr_Base_Query.php
index 72c45df..3573546 100644
--- a/Solr_Base_Query.php
+++ b/Solr_Base_Query.php
@@ -426,7 +426,7 @@ class Solr_Base_Query implements Drupal_Solr_Query_Interface {
       $alias = isset($this->field_map[$name]) ? $this->field_map[$name] : $name;
       // Get the values for $name
       $extracted = $this->filter_extract($filterstring, $alias);
-      if (count($extracted)) {
+      if (!empty($extracted)) {
         // A trailing space is required since we match all individual
         // filter terms using a trailing space.
         $filter_pos_string = $this->filterstring . ' ';