Ninth Doctor (Scream of the Shalka)

A possible ninth incarnation of the Doctor was seen by the Eighth Doctor in the Tomorrow Window. He sucked on an asthma inhaler and resembled an aristocrat with a high forehead and shallow-sunken eyes. (PROSE: The Tomorrow Windows)

Daughter of Mine was visited several times by an incarnation of the Doctor she described as a "tall white aristocrat". (AUDIO: Shadow of a Doubt)

Behind the scenes
As confirmed by Jonathan Morris, this is clearly a description of the Ninth Doctor from Scream of the Shalka.