Fisken is an ex-captain of the West of Scotland club and assistant Currie coach Campbell Reynolds said: “Alex has been moved through by his job and has the chance to stake a claim for a settled run after scoring against Melrose last week.”
On the bench for Currie are under-20 prospects Michael Vernal, a hooker, and Jack Broadly, a centre who joined over the summer from Watsonians and have been waiting patiently for a run.
Simeon James fills the stand-off slot after Jamie Forbes joined the injured list. Another player who has filled the pivotal role this season, Adam Hinds, is listed on the wing but faces a late fitness test.
Boroughmuir call up Malcolm Clapperton, Ross Bradford, David Reekie, Robin Hislop, Kian Coetze, Ally Macleod and Iain Moody following their loss to Aberdeen Grammar.
Edinburgh Accies head for Heriot’s with coach Simon Cross insisting: “We are taking the Cup very seriously and are looking forward to keeping the momentum in our season going.”
Hamish Watson’s return to the back row after turning out for Edinburgh against Ulster in Belfast allows Dan Teague to be rested with the captaincy switching to Greg Campbell. Johnny Adams gets a start at scrum half and Andrew Findlater is fit to resume at second row.
For Heriot’s, the tie is a chance to avenge a recent league defeat by Accies after they had led 26-6 at the interval.
After making his comeback from a lengthy injury break at flanker, Fraser Brown returns to the hooker role from which he led Scotland under-20s, while Sam Hidalgo Clyne and OJ Brown form a new half-back combination.
At Myreside, Watsonians put a ten-match unbeaten run on the line against Lasswade. Captain Mark Rennie is unavailable, so Ben Di Rollo takes the armband and Jonny Duthie steps into second row against opponents expected to field ex-’Sonian players Jamie Blackwood, Gavin Brown and Bernie Hennessey.