If Craig Casey is fielding questions about whether or not he's keeping tabs on the latest scrum-half hot-shot, it's probably a sign that Ireland's long-term future behind the scrum is quite healthy.

The 22-year-old has been one of Irish rugby's major prospects in the last two years, establishing himself as the probable successor to Conor Murray at Munster, as well as earning three Ireland caps during 2021.

Step forward Nathan Doak though.

The 19-year-old Ulster scrum-half looks already physically ready for whatever senior rugby can throw at him.

Dubbed the province's 'Ginger Pienaar', the teenager has featured in all four of the Ulster's bonus-point wins to start the season, scoring three tries, kicking 22 points and showing the kind of form that has made almost everyone sit up and take notice.

And while the Ulster prodigy wasn't named in Andy Farrell's squad yesterday for next month's Test matches with Japan, New Zealand and Argentina, it seems inevitable that Doak (below) will gatecrash the party sooner or later.

Casey looks set to add to his three caps next month though, equally impressing in his three outings for Munster this season, and is named alongside Murray and Jamison Gibson-Park in Farrell's squad.

The Shannon man was asked whether he had been looking over his shoulder at the arrival of Doak on the scene this season, and while he says he stays up to speed on what the other scrum-halves in Ireland are up to, it's for study rather than fear.

"Not really that I would 'keep an eye' on what they're doing," he says. "I try and take the best from other scrum-halves' games.

"I'm not too interested in what's going on outside the other provinces really. I try and take the best from the best and learn off them."

Casey seems to be very much in Farrell's Irish plans, with a zip to his passing, but is striving to improve on what he's shown in his first three internationals.

"In ways I haven't been overly pleased with everything I have done (with Ireland)," he says.

"I definitely have been happy with some things I have done, I definitely have a few work-ons as well so obviously with this Saturday coming I want to show those in the game, make up or learn from the mistakes I’ve made, and obviously keep doing what I’m doing well."

The Casey v Doak debate has a lot of road left in it, so it's probably more pressing for the Munster man to focus on the job at hand; turning Munster's 21 shirt into a 9.

The gap in the province's scrum-half pecking order is continuing to shrink as Casey grows into the game, and Murray's extended summer break has given Casey a big opportunity to impress.

Starting three of their four opening games - and rested for the away trip to Scarlets - Casey has been sharp and snappy, particularly in their season-opener against the Cell C Sharks, where he was named Man of the Match.

With Murray now back in full training and available for selection for this Saturday's trip to the Ospreys in the United Rugby Championship, Casey is hoping he has given Johann van Graan and his management team some food for thought.

"It's been great. I feel like I've come on a good bit over the last eight weeks. I'm glad I could show that a bit over the last few weeks.

"Minutes on the pitch are brilliant, you're making mistakes, you're making good things happen.

"I think you get into a state of flow when you play a few games in a row, you learn off your mistakes and you learn off the things you do well so I think playing the three games, seeing what I have and haven't done well, seeing what I need to work on has been good and I enjoy it.

"Definitely during the pre-season I tried to put an onus on my running game as well as my passing game and then with Bomber (Andrew Conway) I definitely worked on that with him over the last few weeks. Something that he's always chirping on about, be on my inside, be on my outside, just show the space and, in fairness, he saw the gap around the ruck and I was able to take the first defender and then let him do the rest."

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