The TARDIS had absolutely no interest in this 'death match' and had long-since crumpled up the letter informing her of her appointment. She'd seen what had happened to Oliver and had no intention of allowing someone to coerce her into the same scenario. (It didn't help she considered herself impervious, either, and therefore the threat of death was moot.)

So it was when she suddenly appeared in the centre of the arena without so much as a 'by your leave,' the ship was honestly surprised. Whatever had the ability to teleport her against her will was strong, if nothing else, and perhaps worthy of some consideration. All she could manage, however, was an icy glare toward the empty throne next to which sat Caleb as she waited for her opponent.