diff --git a/psc-flink/src/main/java/com/pinterest/flink/connector/psc/source/metrics/PscSourceReaderMetrics.java b/psc-flink/src/main/java/com/pinterest/flink/connector/psc/source/metrics/PscSourceReaderMetrics.java
index 4a1e8d4..3d2c6d8 100644
--- a/psc-flink/src/main/java/com/pinterest/flink/connector/psc/source/metrics/PscSourceReaderMetrics.java
+++ b/psc-flink/src/main/java/com/pinterest/flink/connector/psc/source/metrics/PscSourceReaderMetrics.java
@@ -239,7 +239,7 @@ public void removeRecordsLagMetric(TopicUriPartition tp) {
      * bytes-consumed-total and count it towards the counter.
      */
     public void updateNumBytesInCounter() {
-        if (this.bytesConsumedTotalMetric != null) {
+        if (this.bytesConsumedTotalMetric != null && this.bytesConsumedTotalMetric.metricValue() != null) {
             long bytesConsumedUntilNow =
                     ((Number) this.bytesConsumedTotalMetric.metricValue()).longValue();
             long bytesConsumedSinceLastUpdate = bytesConsumedUntilNow - latestBytesConsumedTotal;