Technician (The Five Doctors)
From Tardis Wiki, the free Doctor Who reference
During the crisis in the Death Zone on Gallifrey, the Time Lord technician was asked by Lord President Borusa to free the Fourth Doctor from a time eddy in order to join his other incarnations. He was unsuccessful. (DW: The Five Doctors)
The technician wore a similar costume to that of Co-ordinator Engin, but performed a role much more akin to that of an earlier technician. (DW: The Three Doctors)