diff --git a/prometheus_api_client/metric.py b/prometheus_api_client/metric.py
index 3ff971e..0ecb899 100644
--- a/prometheus_api_client/metric.py
+++ b/prometheus_api_client/metric.py
@@ -54,10 +54,9 @@ def __init__(self, metric, oldest_data_datetime=None):
             self.metric_values = metric.metric_values
             self.oldest_data_datetime = oldest_data_datetime
         else:
-            self.metric_name = metric["metric"]["__name__"]
+            self.metric_name = metric["metric"].pop("__name__", None)
             self.label_config = deepcopy(metric["metric"])
             self.oldest_data_datetime = oldest_data_datetime
-            del self.label_config["__name__"]
 
             # if it is a single value metric change key name
             if "value" in metric: