FRANCE| Born | Dec 10, 1993 Bourg-Saint-Maurice, FRANCE |
| Age | 32 years old |
| Size | 1.77 m |
| Arrival(s) | |
| End of contract | 2029 |
| Numbers | 28 |
| Career | |
Born of Franco-Croatian parents in December 1993 in the French Alps, at Bourg-Saint-Maurice, Adrien Thomasson started his sporting career in his hometown club, with FC Haute Tarantaise, whilst also actively pursuing winter sports, mainly alpine skiing (where he specialised as a teenager in Giant Slalom)
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In 2008, Thomasson joined the Academy at Annecy, aged 15. During his development, the young midfielder had numerous trials with professional clubs, such as Guingamp, Lorient and Saint-Etienne. In 2011, he joined Evian Thonon Gaillard, starting with the U19s, before achieving promotion to the Reserves in CFA2 (French fifth tier.)
Towards the end of the 2011/2012 campaign, First Team boss, Pablo Correa, gave him his first appearance as a professional, on 6th May 2012, against Corsican side AC Ajaccio, aged 18. Alas, the following 2012/2013 season would prove to be less convincing for Thomasson. First, he no longer figured in the plans of his coach, deemed to be not ready for professional football, and then he lost his father too. The experience, in the words of the player himself, "toughened him up" considerably.
In order to obtain some gametime, the young Savoyard player left his native region for the first time and signed on a season-long loan in Brittany with Vannes OC (Playing in the French 3rd Tier). His 2013/2014 season as a semi-professional would prove to be a success for Thomasson, both from a personal and from a professional perspective. Despite the relegation of Vannes at the end of his loan spell, Thomasson finished with a creditable record of 9 goals and 8 assists in 30 appearances for Vannes.
Evian planned to loan him out for a second time for 2014/2015, but their manager Pascal Dupraz decided to bring him back into the professional group, and didn't regret his decision. He would score his first goal as a professional footballer on 10th January 2015, at home to a certain Stade Rennais.
In June 2015, Thomasson was given a new challenge with FC Nantes, having made 27 appearances as a professional with Evian. His first goal for the Canaries came in a friendly against Lorient, and he went on to establish himself over three seasons at the club. 110 matches in Green and Yellow, 13 goals to his name.
His next club would be in the East of France, with Racing Club de Strasbourg, signing a three-year deal with the club in Alsace. He would also become a key player in their setup, amassing 156 appearances, with 28 goals to his name by the time he ended his fifth campaign at the club. He would then swap one Racing Club (Strasbourg) for another, signing for Northern France's Racing Club de Lens in 2023, in a deal with 3.9 Million Euros with a potential 500,000 Euros in bonuses.
At Lens, he would score in the famous victory against Arsenal in the Champions League in the October of the year he joined them. He ended his time at Lens as Club Captain, helping his team to lift the French Cup against Nice at the Stade de France, just a matter of a week before signing for Stade Rennais on a free transfer on 28th May 2026, the Red and Blacks' first new recruit of the 2026 Summer transfer window.