diff --git a/logger.go b/logger.go
index cf92553a..86bb8daa 100644
--- a/logger.go
+++ b/logger.go
@@ -309,6 +309,6 @@ func LoggerWithConfig(conf LoggerConfig) HandlerFunc {
 
 		param.Path = path
 
-		fmt.Fprint(out, formatter(param))
+		_, _ = io.WriteString(out, formatter(param))
 	}
 }