If ever there was a five-year overnight sensation it is assuredly Thomas Clarkson. He made his Leinster debut in August 2020 but went into this campaign with less than 20 starts under his belt and as his province’s third choice tighthead. Yet there he was on Tuesday night in the Marvel Stadium mixed zone after the 24-19 win over the Pasifika XV, a bona fide British & Irish Lion.
No one seemed more incredulous as well as delighted than the 25-year-old himself, for he freely admitted he wouldn’t have thought all of this was possible when he was named as one of the additional, or development, players to train with Ireland’s squad last November, before making his debut against Argentina off the bench, backing it up against Fiji, and then playing in four Six Nations games, starting against Wales. Clarkson is eligible for Italy on his mother’s side and also revealed he was approached by Italy at the start of last season.
“I wasn’t even really expecting to play in that. So, to get a cap I was delighted.
Andy Farrell's Lions fire the first shot in Australia
“The Six Nations; I was happy enough with how it went. I wouldn’t have said I set the world alight or anything. So, to then play well for Leinster at the end of the season and come in here, it’s pretty mad.”
READ MORE
As recently as January 2025, Clarkson was playing an AIL Division 1B game for Blackrock.
“I made my Leinster debut five years ago now, so I’ve been waiting a long time. So, the fact that when it has come, it’s all come at once is a bit crazy. Because I went through a good few years of not getting a sniff in at all really.”
It’s been a Lions tour of an unprecedented and, frankly, unexpected bounty for Irish tightheads, three of them making the tour. And two of whom are inextricably linked. Had it not been for the calf and hamstring issues which restricted Tadhg Furlong to just seven games for Leinster and one for Ireland, Clarkson would never have had the opportunities that came for province and country.
Even so, after adding three more Champions Cup pool games to his one outing before this season, Clarkson didn’t make the Leinster 23 in their European knockout games.
But with Furlong sidelined again, Leo Cullen started Clarkson in their round 18 game against Glasgow. “It all kind of just clicked and then kept that momentum going. That was the first game when I thought: ‘That was a proper performance’.”
David Humphreys has now lifted his moratorium on the provinces signing props from abroad and although Furlong’s injury woes have been a factor, Clarkson’s own account of his growth this season shows how Irish players can learn from overseas acquisitions like Rabah Slimani.
“I’ve been kind of understudy to Tadhg for a good few years now. He’s consistently been probably the best tighthead in the world over the last few years. It’s been unbelievable being there, just around him.
“Rabah’s come in and probably offered something a bit different, where he’s 100 per cent scrum. Tadhg obviously has an array of different stuff that he brings to it, whereas Rabah, when you’re scrumming against him in training, it’s all or nothing against him. It’s been a different kind of experience with him, but I’ve felt I’ve come out the other end well.”
Clarkson retained his starting place at tighthead in the URC quarter-final, semi-final and final wins, before playing against Georgia and Portugal. That Saturday night in Lisbon, he thought his breakthrough season was done until he received a text from Andy Farrell at 3am.
“We were on a night out; I had to go home straight away. But yeah, some text to get. It was like: ‘ring me when you’re awake’, so I said: ‘Oh yeah, grand’. Then Paulie [O’Connell] rang me and was like: ‘Ring him right now’. So yeah, I had to just compose myself and go outside. I told Jack Boyle and then just legged it.”
Sadly, social media can be a nasty world, and on foot of the backlash to him and Jamie Osborne being called up, Clarkson opted to ignore it.
“I feel like the last few weeks in Leinster, before the semi-final, was fairly negative. I just tried to use that as a bit of motivation. I knew, just because Jamie got called in right before me, there was a bit of backlash to that. So, I knew it was going to be even more when I got the nod. So yeah, I just tried to stay away from it.”
“It was a bit of a shock at the start, to be honest. You grow up using social media. It was hard to step away from it. But I just had to get rid of a lot of that.”
Clarkson admits that linking up with the Lions at short notice was a good deal easier for him than the late Scottish call-ups given his familiarity with so many players and coaches, not least Andy Farrell and John Fogarty.
On Tuesday morning Fogarty told Clarkson that his form for Leinster merited his call-up and encouraged him to continue that form into the match that night, so building up his confidence.
“I felt like I was chasing my tail a little bit, but happy enough with the scrum and I made a few tackles. It was a good start.”
To make Clarkson’s landmark night even better, his father Finbarr made it out in time for Tuesday’s match. “I think he knew if he was going to be here for any game, it would be this game. So yeah, he legged it down.”
All the while in the mixed zone, he still had his Lions cap in his grasp, which had been given to him by Ieuen Evans. “It’s crazy, 886,” he says, of his number in Lions’ playing history. “I didn’t even know they did caps if you don’t play in the Test.”
He’s a Lion now all right.
