In a sense it doesn't matter because of Riise's proven ability to score for Chelsea while playing for Liverpool. However, to make it a bit more painful for Liverpool, let's say he comes on for Everton and heads in a cross from Donovan (since they've not been too fond of the "Yanks" recently).
Upon reading this question I had two thoughts:
My favorite moment of the season last year was when Cahill and Lescott combined to head it past Reina and Cahill jumped on Lescott's back and pointed up at the Kop laughing. That being said, I wouldn't mind it being Cahill because he has been such...