He has come a long way to get to this point but knows there are still plenty of miles to be travelled if he is to convince Ireland head coach Joe Schmidt he is worthy of a sustained career at this level.

“I guess I just need to keep my head down and keep working hard and learning from all the world-class players around me,” Sweetnam told Irish Examiner Sport this week. “Just keep getting better and hopefully more opportunities will come.

“I’ve been in Ireland camps before but this is my first time being in every day and I’m getting a feel for the environment, being nailed on with the detail and not being late for meetings and stuff.

“As I said, keep working hard, keep working on my high ball, getting that cradle right and defensively with Andy Farrell, that’s massive as well. I’ve got to keep learning and improving.”

Sweetnam is off to a solid start, making the most of the six minutes he was given off the bench against the Springboks and executing a much-praised pick up on the run down the right touchline to receive a Joey Carbery crossfield kick pass in the build-up to Jacob Stockdale’s try in the left corner.

“You practice those things in training but I was thinking after that maybe I could have grubbered it through and maybe score but we scored off it anyway when Jacob got over in the other corner. So it was a win-win.

“I was pretty nervous (before getting on), kept looking up at the clock, like, ‘will I be used?’ but when Paul (Dean, Ireland team manager) called me in I was ‘okay, better get ready here’.

“The game was won but the pressure wasn’t off, really. I still needed to go out there and not make any mistakes. It was my first experience of Test rugby and by that stage I really wanted to get on and do well. It was nice. I did grand.”

His phone has not stopped buzzing since, much like its owner, for whom matching his brother Clinton’s Ireland hockey cap is also a point of pride.

“It was nice to equal him there last weekend,” he said. “My parents, my brother and my sister, my aunties and uncles and my girlfriend, Thea, was over as well from Scotland. I’m really excited and a bit nervous but it will be nice after experiencing a bit of it last week and to be getting my first start now will be pretty special.

“Even walking out of the Shelbourne and getting clapped onto the bus, I was getting quite emotional about that, didn’t know where to look, so I’m looking forward to doing that again and running out in front of a packed Aviva, getting more involved as a starter. It’s pretty special and hopefully, it goes well.”

It seems an obvious comparison to make, that for Sweetnam, last Saturday’s entrance drew parallels with a similar situation at Croke Park in 2012, when as a 19-year-old Dohenys clubman he was sent into the fray of an All-Ireland hurling semi-final by Cork manager Jimmy Barry-Murphy.

Not so obvious to the man himself, not at first at least.

“They were two different games but I think subconsciously maybe it did help a bit. I think I was more nervous coming on on Saturday than I was back then when I was younger and there were fewer expectations. So it might have helped but I don’t know. It’s a long time ago now.”

As was Sweetnam’s decision to dedicate himself to the objective of a life in professional sport at the expense of a potential inter-county hurling career.

“I was playing Munster Under-20s around that time and kind of undecided at that stage but I think it was after that day in Croke Park that I made the decision to stay with rugby.

“I’d been offered an Academy contract with Munster and I knew it was a risk but at the end of the day I wanted to play professional sport and I’m delighted now that I went on that path.

“It’s been a long road to here. There were stages in the Academy where I was like, ‘oh, have I made the right decision?’ I was subbing for the A team and there was a lot of lads ahead of me and it made me question myself but I don’t even look back now. It was definitely the right decision.” There may still be time for hurling. After all, former Munster and Ireland scrum-half Tomás O’Leary made a successful comeback for East Cork club Erin’s Own this summer.

“I haven’t seen him play but I’ve heard a few stories all right! They went all the way to a county junior final. Tomás is a gas man,” smiled Sweetnam.

“Would I do the same thing? I’ll see how the body is when I retire but I wouldn’t rule it out.”