With Paddy Jackson World Cup-bound, Ian Humphreys sidelined with a hamstring injury and new number 10 recruit Sam Windsor also a regular visitor this week to the physio room, Marshall could be call to fill a role he last played in his early days at Ballymena Academy.
Prop Callum Black and number eight Roger Wilson are also out for a few weeks yet, although Nick Williams has now served his ban from last season and is available for the game.
Temporary head coach Neil Doak said that Humphreys will certainly miss out.
“It’s a little bit early for Ian.
“We will see what he gets through today, but it is highly unlikely that he will feature. As for Luke, he may well have to fill in (at fly-half),” said Doak.
Doak is relishing a return to competitive rugby despite some poor results pre-season.
“We were beaten in both our two warm-up games against Leinster and Edinburgh, but the positives outweighed the negatives
“ We did very well in those games to get into the right areas of the pitch. We will just have to be more clinical in our application.”
Doak also expressed satisfaction at seven Ulster players making the World Cup squad.
“I’m delighted for those players.
“There were quite a number of other players involved in the large Irish squad and it shows that quality of players we are producing here.
“There were other players like Andrew Trimble, Craig Gilroy, Dan Tuohy and Rob Herring who missed out on World Cup selection, but you never know, they could be involved yet.”
Meanwhile, Ospreys have signed Oliver Tomaszczyk on a short-term contract.
With Aaron Jarvis this week confirmed in the Welsh Rugby World Cup squad and Daniel Suter ruled out of action for the opening rounds of the new Pro12 campaign, the 28-year old tight head offers temporary cover in a key position for the Welsh region.