Well, don't silence so head on, use it when all your interrupts are gone like Mind Freeze, Hungering Cold, or Death Grip (those two can stop a cast). Never let the disc priest cast anything other than Penance, you want to burn out his mana, use AMS and predict when he'll use the next fear, or lichborne, or get that weapon enchant, when you can't interrupt his cast cause' he popped Inner Focus, pop Death Grip or Hungering Cold and wait out the anti-interrupt. Other than that, you can just easily go with your regular rotation while using Blood Tap to keep up with Pillar of Frost or an extra Necro. And if it was the leader of gatekeepers (Androniicus) he's skilled at disc, so don't expect a easy win lol. Anyways, you can get help from Jyx but I wouldn't suggest it, she has to bug exploit to win duels (haste bugging) but ends up losing. Wish I had that match on video to keep me laughing.