diff --git a/src/objective-c/GRPCClient/GRPCCall.m b/src/objective-c/GRPCClient/GRPCCall.m
index 0eb10656ddc3ea916ebe4fe02d5e54185ad48461..e9678f38a9c46604779b7927f95dbfaeddcff962 100644
--- a/src/objective-c/GRPCClient/GRPCCall.m
+++ b/src/objective-c/GRPCClient/GRPCCall.m
@@ -76,7 +76,6 @@ NSString * const kGRPCTrailersKey = @"io.grpc.TrailersKey";
   NSString *_host;
   NSString *_path;
   GRPCWrappedCall *_wrappedCall;
-  dispatch_once_t _callAlreadyInvoked;
   GRPCConnectivityMonitor *_connectivityMonitor;
 
   // The C gRPC library has less guarantees on the ordering of events than we