The Cardiff academy product was one of five uncapped players in the squad and will be joined by 10 of his club team-mates in the national set-up, including housemate Owen Lane.
Thomas’ call-up came on the back of a hugely impressive Guinness PRO14 Rainbow Cup campaign where he featured in all five matches and displayed his versatility by playing at outside-half, inside centre and full-back.
The playmaker says representing his country would be a dream come true, but insists there is no time to get carried away as he looks to earn a spot in Wayne Pivac’s starting line-up.
“We first heard around 10.50am and there was a bit of a delay on the announcement which kept everyone on edge,” said Thomas.
“You always know there is a slight chance a youngster would get called in for a summer tour but there has been a lot of good competition in the centre so I wasn’t expecting it at all.
“It’s a massive moment for me and a bit nerve-wracking if I’m honest.
“This is what you play rugby for and growing up all you want is to play for your country so to be in with the opportunity to do that is tough to put into words.
“It’s a feeling I never thought I’d quite experience. You’ve always dreamed of playing for Wales, but just to be named in the squad is something that’s quite hard to get my head around.
“There is a big training camp coming up so now I want to make sure I do my best throughout that camp and hopefully the rest will take care of itself.
“I’m ecstatic and over the moon just to be involved in this environment but once I’m there the natural competitiveness will take over.
“I’ll just want to keep fighting and pushing forward and hopefully put my hand up for selection.
“It would be massive if we were to have crowds back in the summer, especially for the boys who could get their families to watch them play. It would be pretty special.”
Thomas showed plenty of promise in the Rainbow Cup, forming an impressive partnership with fellow Wales squad members Jarrod Evans and Willis Halaholo.
He admits the regular game time has been highly beneficial and hopes his link-up with Evans and Halaholo can continue on the international stage.
“The Rainbow Cup has been massive for me. The biggest factor is being able to play week-in, week-out over the last six or seven weeks,” added the former Cardiff and Vale College pupil.
“I’ve really enjoyed the Rainbow Cup and even though I’ve played in different positions I’ve pretty much played 80 minutes for a number of weeks in a row.
“It’s a real help to have familiar faces around me in the camp, especially with Jarrod on my inside. He generally steers the ship so it will be good to have that familiarity.
“I really enjoy playing with Willis and it’s something I never really thought I’d do much of because we both tend to play at 12.
“But it’s been really exciting and enjoyable to play alongside both Willis and Jarrod.
“The three of us have worked quite well together and put together decent performances alongside each other.
“Distribution and playmaking is something I feel I can bring as well as being that second playmaking option. It’s probably been helped by the fact I grew up playing as a 10. Hopefully that’s something I can deliver.
“To be realistic it’s about getting as many minutes on the field as I can at this stage.
“So anywhere I’m put I’ll make sure to put my best foot forward and will just be happy to play.”