"Oh, I'm sure I'll be fine," the Doctor answered casually. "We'll just have a talk. Catch up on things and make one or two details clear."

After all, while he'd heard the Master was here, it was another matter to find him. At this point the Doctor was largely working off the assumption that the Master would, sooner or later, contact him somehow. He had to know the Doctor was here after all, and there was no way the other Time Lord would pass up the chance to point out his presence to the Doctor.