Leela nodded, agreeing with the plan. "Romana could be the best choice, but you know how clever she is. She may know she is being sent to distract him. Perhaps you or the other Doctor could try talking to him, and if that does not work, then have Romana try." Leela fell silent as she pondered that for some moments. Then suddenly, a light bulb went off.
"I have it!" She exclaimed a bit loudly. "You or your other should talk to him, perhaps saying something that will lead him to talk to Romana, even meet her somewhere. I could then plant your device in his living space. That way neither the Master nor Romana are the wiser to our plans." Well, at least Leela thought was a good plan. It would mostly depend on how good the Doctor was at talking to the Master without seeming suspicious.