My memory’s not what it was.
Couple that with an extreme shortage of memorable Aberdeen players over the past 30 years and it causes a problem.
I have no memory of Clark Robertson playing for the Dons at all.
Despite a seive like memory similar to your own, I do remember one robust challenge from Mr Robertson near the corner flag at the South/ Merkland corner. If my memory is correct it was more memorable because he took out a hun in making the tackle.