Guard (The Savages)
From Tardis Wiki, the free Doctor Who reference
A guard was one of the Elders. He was on guard outside the citadel when Steven, Dodo and Chal planned to rescue the First Doctor.
He was unconcerned when he heard Steven moving, thinking it was Exorse returning, allowing Steven to sneak up on him and stun him with Exorse's light gun. (TV: The Savages)