Real Madrid have completed the signing of 19-year-old midfielder Sergio Martinez from Racing Santander, with the Spanish club confirming the deal on Monday, 31 August. Madrid activated Martinez's €3 million release clause and have tied the teenager to a contract running through June 2030.

Who Is Sergio Martinez

Martinez had already made an impression at the start of Racing Santander's new season, scoring in the club's opening league fixture before his departure was confirmed. At 19, he arrives at the Santiago Bernabéu as a development signing — a low-cost bet on a player whose early-season form evidently caught Madrid's recruitment team's attention. The €3 million fee, activated via his release clause, represents minimal financial risk for one of the world's wealthiest clubs.

Mourinho Declares Squad Closed

The arrival of Martinez comes as head coach José Mourinho has publicly declared the club's summer transfer business effectively over. Speaking ahead of Real Madrid's delayed La Liga opener against Real Sociedad at the Santiago Bernabéu on Thursday, the Portuguese manager said he is satisfied with the group at his disposal.

'For me, the squad is closed, but the market is still open; you never know if a player will come and say, 'I've been benched twice, and I want to leave.' In theory, no (more deals)... but something could always happen... In my head, the squad is closed, and I have not asked for anyone. I am very happy with the players I have,' Mourinho told reporters.

Midfield Rebuild After Modric and Kroos Exits

The signing of Martinez reflects the scale of Madrid's midfield restructuring this summer. The departures of Luka Modric and Toni Kroos — two of the most decorated central midfielders of their generation — have fundamentally altered the engine room at the Bernabéu. Mourinho now faces the task of reshaping the unit around Aurélien Tchouaméni, Eduardo Camavinga, Federico Valverde, and Bernardo Silva.

Notably, Mourinho has indicated he does not intend to lock his midfielders into rigid positional roles. 'I don't want to identify Tchouaméni as the No. 6, Camavinga as the No. 6, Fede as the No. 8, Bernardo as the No. 10... things dilute during games,' he said. Real Madrid had also been linked with further midfield reinforcements during the window, particularly after missing out on Rodri, who reportedly chose to join Barcelona.

Balancing the Attack: Mbappé, Vinicius, Bellingham

Beyond midfield, Mourinho acknowledged the tactical puzzle of integrating three elite forwards — Kylian Mbappé, Vinícius Júnior, and Jude Bellingham — into a cohesive starting XI. 'The problem for a coach is not having top players, or what if one of them gets injured. I've had that problem in recent years, not being at the best clubs in Europe. I want all three of them together; their positive qualities compensate for any lack of tactical understanding they might have. That's where I can help,' he said.

As the La Liga season begins, Martinez's integration into Mourinho's squad will be closely watched — both as a signal of Madrid's long-term midfield planning and as a measure of how the club intends to manage depth across a demanding European campaign.