The 20-year-old centre-back from Lasarte, who turned in a commanding 120 minute performance in Real Sociedad's Copa del Rey final victory over Atlético Madrid — a penalty shootout success after a 2-2 draw — has emerged as one of the most coveted players in La Liga this summer.
Barcelona sporting director Deco met informally with his agent Iñaki Ibáñez last week to assess his availability, while Real Madrid have had scouts watching him for months.
Martín signed a contract extension until 2031 last September, with a €50 million release clause inserted to deter approaches. Real Sociedad have made clear to both clubs that the full clause must be paid.
Speaking to AS, Martín addressed the speculation directly and without hesitation.
"I have it clear. I want to be here for as long as possible, I want to be here, in my home, because this is the place that has given me everything. I am calm and hopefully I can be here for many years and win many titles like the Copa."
On the reports linking him to the two biggest clubs in Spain, he was phlegmatic.
"It is impossible for it not to reach you because everyone talks about it. You are outside and whether you like it or not you see it — even my friends tell me because they are looking at things all day. In some way it ends up reaching you. But as I say, I remain focused on working with Real Sociedad."
He was asked whether the fans could genuinely feel relaxed.
"That's right. Totally."
The Copa del Rey final performance that sparked much of the current interest saw Martín excel against an Atlético attack that had already knocked Barcelona out of the competition — a test that effectively announced him to a European audience. He has made 28 appearances for Real Sociedad this season, operating in the 90th percentile for Spanish centre-backs across multiple defensive metrics.
Martín came through the youth system at Real Sociedad alongside Lamine Yamal and Pau Cubarsi in Spain's junior national teams, and a senior call-up under Luis de la Fuente is considered imminent if his form continues.