diff --git a/lib/private/Console/TimestampFormatter.php b/lib/private/Console/TimestampFormatter.php
index 59e480b39e8d8..c25ed578805af 100644
--- a/lib/private/Console/TimestampFormatter.php
+++ b/lib/private/Console/TimestampFormatter.php
@@ -99,6 +99,11 @@ public function getStyle($name) {
 	 * log timezone and dateformat, e.g. "2015-06-23T17:24:37+02:00"
 	 */
 	public function format($message) {
+		if (!$this->formatter->isDecorated()) {
+			// Don't add anything to the output when we shouldn't
+			return $this->formatter->format($message);
+		}
+
 		$timeZone = $this->config->getSystemValue('logtimezone', 'UTC');
 		$timeZone = $timeZone !== null ? new \DateTimeZone($timeZone) : null;