Leinster will be playing a waiting game over the fitness of Jonathan Sexton, with the Ireland fly-half nearing his return from a hamstring injury.
Sexton is in line to make a comeback from the problem in time for their second Champions Cup pool clash, against Montpellier on the road.
His replacement last weekend was Joey Carbery, who played well against Castres in the win, with head coach Leo Cullen giving an update.
"Hopefully Johnny will be OK. He was training last week, going through his rehabilitation and has been jogging over the weekend so we will wait to see how he progresses over the next few days," Cullen told EPC Rugby ahead of their difficult fixture at Altrad Stadium on Sunday.
On their 33-15 victory over Castres at the RDS, a pleased Cullen added: "We were delighted with the outcome and it was four more points from the opening game than we had at this stage last season.
"But we're actually frustrated because we feel we left a lot of opportunities out there. So there is stuff to work on before we move on a really tough challenge in Montpellier.
"Defending the driving mauls is going to be a big thing in this pool because we have two French teams in Castres and Montpellier, as well as Northampton, who are all very strong in that area.
"We were a bit frustrated because we got caught on the hop with one drive in particular [against Castres] so it's an area we definitely need to be a bit better at given we're facing French teams for two weeks in a row."