The 20-year-old second row has agreed a three year deal with the region that will tie him to the Liberty Stadium until the end of the 2017/18 season
Thornton learned his rugby at Bonymaen RFC, Cefn Hengoed School and Gower College. He then played for Swansea, Bridgend and the Ospreys age grade teams, winning honours at Wales Under 18 and Under 20 levels.
He made his senior Ospreys debut against Saracens at The Gnoll in the LV= Cup last November and has since gone on to make seven appearances. He captained Wales throughout this year’s Under 20 Six Nations Championship and Junior World Championship.
“Signing a professional contract has always been my first goal coming through the ranks at the Ospreys. It’s a real achievement for someone of my age and something that I can be proud of,” said Thornton.
“Looking back at the last year, it’s been really incredible. Last summer I would have said that I was hoping to train with the senior team and get some LV= Cup games, but it’s been far better than I could have hoped for – playing in the PRO12 semi-final, captaining Wales and everything.
“Making my first PRO12 start in Edinburgh was tough. It showed me how high the required standard is if I’m going to play regularly, but it also gave me a taste and I want to play more for the Ospreys.
“I know that I’ve got a lot of hard work ahead of me and that I can’t take anything for granted. This is my home region, so I get a buzz from being involved and training with people like Alun Wyn Jones.”
