Johnny Sexton has been Ireland's driving force for a number of years, however, Alan Quinlan believes the lack of a viable alternative is a concern for Andy Farrell.
Quinlan, who joined Ger Gilroy and Nathan Murphy on Monday's OTB AM, was quick to praise the impact that Sexton has had on Irish rugby for well over a decade, but he hopes Joey Carbery can return from injury to push the Ireland captain to maintain his form.
"Overall, what Johnny Sexton has brought has been phenomenal," Quinlan said of the Leinster fly-half.
"His consistency in his performances, his ability and aggression, and his leadership in the team has been second to none."
Despite Sexton's continued excellence, he is now well into his thirties.
While Quinlan believes that Sexton is still performing at a high standard, he needs to be challenged on a regular basis and Ireland need to plan for his succession.
Joey Carbery has the potential to push Johnny Sexton
At this juncture, no one has come as close as Carbery to competing with Ireland's captain for a place in Andy Farrell's first 15.
"No matter what level and what [a great] player you are, you need to be pushed and challenged," Quinlan continued.
"Carbery was the one who was a real live contender to take Sexton's place but the injuries have tormented him so hopefully we can see him back as well."
Carbery suffered a setback in his rehabilitation of an ankle injury, and Munster head coach, Johann van Grann has said that they would not rush him back and risk damaging the ankle further.
"As disappointing as the latest news is, we have Joey at the centre of it all, going through this, and doing everything right in making sure that when he returns to the pitch he stays on the pitch," van Graan said in August.
On that decision, Quinlan is in agreement with van Graan, believing the longevity of the player is paramount.
That being said, should Carbery make a return in 2021 it would be a massive boost for Irish rugby.
"What would be brilliant for me, and everyone involved in Irish rugby, [would be] if we could see Carbery back on the pitch in January, which is a possibility," said the former Munster captain.
"He is not going to be rushed back from this injury but it would be brilliant to see him back.
Other contenders waiting in the wings
Outside of Carbery, nobody else has really looked like unseating Sexton, however, that does not mean that Farrell has not got quality options in that area of the pitch, according to Quinlan.
Billy Burns, Ross Byrne and Harry Byrne have all shown their talent at fly-half for their respective provinces.
All three have to take another step forward in Quinlan's estimation and that may come as a result of being thrown into the deep end.
"Has the gap closed," Quinlan mused?
"It has not, unfortunately, and that is a concern. Someday if the gap has not closed we are just going to play the next in line and they will have to try and grab onto the jersey."
With the Autumn Nations now behind Ireland, Quinlan believes there was much improvement in the team that faced Scotland on Saturday in comparison to their previous outing against Georgia.
With plenty of positives to take from the performance, the aim now for Farrell's side will be to build towards a positive Six Nations campaign which gets underway in February.