Parker's task at Lansdowne Road will be to mark Brian O'Driscoll - the only man in Britain or Ireland he considers a better outside centre than Taylor.
Parker, who is set to win his ninth cap, said: "I still get freaked out every time I get selected to be honest.
"I still think Mark Taylor is one of the best centres in the world. Every time I get picked I can't believe it.
"So I don't take anything for granted with Wales, especially as I consider Mark the second best centre in the British Isles area. To be selected above him for Scotland I was quite amazed."
And Parker has advised Taylor, who turns 31 at the end of this month, to reconsider his pledge to give up international rugby after this season.
"He is one of the fitter guys in the squad and one of the stronger backs. The only thing that is going to hold him back is injury, so it would be a bit silly of him to give up, especially as the younger guys can learn so much off him."