Why am I getting a leak?

I have an application that contains only this:

- (void)viewDidLoad
{
    [super viewDidLoad];

    //Authenticate Local GameCenter player
    [[GKLocalPlayer localPlayer] authenticateWithCompletionHandler:^(NSError *error)
     {
         [GKTurnBasedMatch loadMatchesWithCompletionHandler:^(NSArray *matches, NSError *error)
          {

          }];
     }];
}

And right away I get a ton of leaks. Am I doing something wrong? I am using ARC.