Sandun

 was a Time Lord technician who piloted the TARDIS that Straxus was using to find the Eighth Doctor. When, after many attempts to find the Doctor, there was a power failure, he was solely concerned with keeping the Dimensional stabiliser working. After this failure they managed to find the Doctor (AUDIO: Tangled Web)

He sacrificed himself to make sure that the Doctor did Staxus' bidding, and show him that his TARDIS was time rammed. (AUDIO: X and the Daleks)