diff --git a/date/date_views/includes/date_views_filter_handler_simple.inc b/date/date_views/includes/date_views_filter_handler_simple.inc
index 8a46253..6a262cf 100644
--- a/date/date_views/includes/date_views_filter_handler_simple.inc
+++ b/date/date_views/includes/date_views_filter_handler_simple.inc
@@ -86,6 +86,17 @@ class date_views_filter_handler_simple extends views_handler_filter_date {
     // All our date widgets provide datetime values but we use ISO in our SQL
     // for consistency between the way filters and arguments work (arguments
     // cannot contain spaces).
+
+    // Group filter case.
+    if (is_array($input)) {
+      // Group filter should take value, min and max from options.
+      $input = $input[$prefix];
+      if (empty($input)) {
+        if (isset($this->options['expose']['identifier']) && isset($_GET[$this->options['expose']['identifier']])) {
+          return str_replace(' ', 'T', $this->date_default_value($prefix));
+        }
+      }
+    }
     if (empty($input)) {
       if (empty($this->options['exposed'])) {
         return str_replace(' ', 'T', $this->date_default_value($prefix));