Jackson calling the shots as Marshall gets big chance to impress
This will be interesting and not just because Sunday games at the Kingspan are exceedingly rare occurrences.
True, tomorrow's clash against Scarlets also marks the remarkably durable Roger Wilson becoming only the second Ulster player to reach the landmark of 200 games for the province, but, again, this is not a major factor in the interest levels being high.
This game is particularly striking as after three wins against sides well outside the top four - admittedly Glasgow have two games in hand - it pitches Ulster in with a Scarlets team very much in the hunt for a play-off place and one which has, until lately, been well used to setting the pace at the top of the table.
So, here we have a real test of Ulster's credentials - but that's not all.
With Rob Herring worryingly out with a hamstring issue, Les Kiss has handed Paddy Jackson the captaincy for the first time.
In addition to being the side's key playmaker, he now has that little bit more resting on his shoulders with both Chris Henry and Darren Cave - perhaps more likely candidates - doubtless there to add advice if required. He is also granted a first start since last month's Oyonnax game in Belfast with Ireland's Six Nations camps having kicked in since then with the 24-year-old being limited to two bench appearances against the Dragons and Glasgow.
If ever there was a time to send Joe Schmidt a message regarding the out-half's added value then now is as good a one as any after, so far, frustratingly not being in any way involved in Ireland's match day squads.
On that subject, Stuart McCloskey not being included tomorrow is also notable.
He was at Ireland's training camp in Mullingar and it may not be unreasonable to assume that McCloskey will be the one heading towards Twickenham if Jared Payne fails to shake off his hamstring injury, though Luke Marshall may beg to differ on that call.
Jackson will have Paul Marshall on the inside - Ruan Pienaar is benched after passing his return to play protocols - and Luke Marshall on his outside with the centre released from being an extra man for Ireland to also make his first start since the try-fest against Oyonnax at the Kingspan.
With McCloskey otherwise engaged, Luke Marshall has his chance to put in another strong display and he lines out alongside the retained Cave while the very useful back three of Jacob Stockdale, Craig Gilroy and Stuart Olding is also selected again after last week's narrow win over Glasgow.
Up front, a lot of attention will be focused on Henry's first start in a month and much will be expected of himself, Wilson and Robbie Diack in the absence of the injured Nick Williams with extra ball-carrying duties doubtless also coming the way of locks Alan O'Connor and Franco van der Merwe.
Hooker John Andrew makes his first senior start while Andy Warwick is in at loosehead prop for Callum Black with Kyle McCall benching again which is where Ian Humphreys comes back into the squad, as does soon to be Munster player Sam Arnold.
There is already some talk about Ulster - who play Zebre twice and Cardiff once in their run-in - not only being shoo-ins for the play-offs but also being in great shape to get a home semi-final.
In that regard, it would be very wrong to automatically assume they are in line for their fourth straight win.
Tomorrow, though, could provide an important indication of what may lie ahead with the safe money being on the home side to maybe not hit their stride again but still prevail.