diff --git a/oauth2_http/java/com/google/auth/oauth2/ExternalAccountMetricsHandler.java b/oauth2_http/java/com/google/auth/oauth2/ExternalAccountMetricsHandler.java
index 8c0073864..fcb656b5d 100644
--- a/oauth2_http/java/com/google/auth/oauth2/ExternalAccountMetricsHandler.java
+++ b/oauth2_http/java/com/google/auth/oauth2/ExternalAccountMetricsHandler.java
@@ -43,7 +43,7 @@ class ExternalAccountMetricsHandler implements java.io.Serializable {
 
   private final boolean configLifetime;
   private final boolean saImpersonation;
-  private String source;
+  private String credentialSourceType;
 
   /**
    * Constructor for the external account metrics handler.
@@ -55,7 +55,7 @@ class ExternalAccountMetricsHandler implements java.io.Serializable {
     this.saImpersonation = creds.getServiceAccountImpersonationUrl() != null;
     this.configLifetime =
         creds.getServiceAccountImpersonationOptions().customTokenLifetimeRequested;
-    this.source = creds.getCredentialSourceType();
+    this.credentialSourceType = creds.getCredentialSourceType();
   }
 
   /**
@@ -69,7 +69,7 @@ String getExternalAccountMetricsHeader() {
         MetricsUtils.getLanguageAndAuthLibraryVersions(),
         BYOID_METRICS_SECTION,
         SOURCE_KEY,
-        this.source,
+        this.credentialSourceType,
         IMPERSONATION_KEY,
         this.saImpersonation,
         CONFIG_LIFETIME_KEY,