Ulster are expecting to be without influential scrumhalf Ruan Pienaar for Sunday’s crunch top of the table Guinness PRO12 game with Scarlets at Kingspan Stadium.
The South African is following the return to playing protocols having suffered concussion during the first half of last week’s 13-10 win over Glasgow Warriors.
Ulster will expect to know on Thursday afternoon if Pienaar will have passed the protocol requirements but could leave a decision until later.
Ulster had an eight-day turnaround and assistant coach, Neil Doak, said with a long turn around than usual it gave them the best opportunity to have those on the injury list fighting fit.
Outhalf, Ian Humphreys, also remained a doubt having missed last week’s game and continuing to go through concussion protocols.
Paul Marshall would be expected to start against Scarlets while Paddy Jackson would be the option at outhalf – although that could also depend on how Jonathan Sexton’s recovery from injury continues with Ireland.
Although this is a down week with no action in the RBS Six Nations, Ireland’s injury profile is such that players Ulster had expected to see back may not return after all.
It had been thought centres Luke Marshall and Stuart McCloskey would be available – both needing some game time – and that would also have allowed some rotation in the backline where Stuart Olding may have been rested.
Doak said: “At the minute we have 10 backs, so if we do not get anyone back that is what we will have to go with.”
Ulster currently top the Guinness PRO12 on points difference from Connacht while Scarlets are a point behind and this is seen as a massive game.
Doak said: “Over this period a lot of teams are playing each other and I think whoever comes out on top will have a decent springboard towards the end of the season.
“There are huge games across the board and we have to pick up points during this period to give us the chance to stay in the top four and ideally the top position.”
Scarlets centre Hadleigh Parkes, who has taken the captaincy reins in Ken Owens’ absence says he is looking forward to Sunday’s challenge in Belfast.
A dramatic last kick victory over Edinburgh last weekend ensured that Scarlets remained in the top four as they face two games on the road over the coming weeks, against Ulster and Edinburgh respectively.
Looking back at the victory Parkes said: “It was very tight but a very important victory.
“We probably didn’t play in the right areas of the field at times and didn’t look after the ball as much as we would have hoped but we really needed the win.
“It’s going to be a big four weeks now and it was certainly good to get one from one.”
Parkes added: “Ulster are a good side and it’s a tough place to go.
“It’s going to be a tough challenge but also an exciting challenge at the same time.
“It’s good that it’s a tight competition but fortunately we’re on the right part of the ladder. We’re definitely still targeting top four. “If we get a couple of good games over the next few weeks we can maybe look at the top two again.”