Real Madrid confirmed on Saturday that Carvajal had sustained a fracture of the distal phalanx of the fifth toe on his right foot, an injury suffered in training on Friday ahead of Sunday's trip to Espanyol.
The club's medical services estimated a recovery period of two to three weeks, which would rule him out of the El ClĂĄsico at the Camp Nou on 10 May and leaves his only realistic chance of a farewell appearance at the season's final home fixture against Athletic Club.
The timing is devastating. Carvajal, 34, began this season having barely recovered from a ruptured ACL that wiped out the majority of the previous campaign.
He had set himself two objectives for the year: to fight his way back into Spain head coach Luis de la Fuente's World Cup plans and to secure a contract extension at the club he has represented for 13 seasons and 448 appearances.
Both are now effectively gone.
The injury will also sash his World Cup hopes and arrives just weeks before the club confirms it will not offer a new contract.
According to Marca, Real Madrid took the decision not to offer Carvajal a renewal some time ago. The combination of his limited availability â 20 appearances in all competitions this season, totalling just 885 minutes â and a deteriorating relationship with head coach Ălvaro Arbeloa, who has preferred Trent Alexander-Arnold at right back throughout the campaign, convinced the club's hierarchy that a parting was the natural conclusion.
His World Cup situation is equally bleak. De la Fuente had already been reluctant to consider Carvajal given his lack of match minutes, and Spain arrive at the tournament in North America this summer as one of the favourites, with Marcos Llorente and Pedro Porro both in strong form in the position. The toe injury removes any remaining argument for his inclusion.
What makes Carvajal's situation feel particularly harsh is the scale of what preceded it. He scored the winning penalty in last season's Champions League final against Paris Saint-Germain and has been one of the defining players of Real Madrid's dominant era â six European Cups, four league titles and a reputation as the most reliable right back in the world across a decade at the top.
His likely final act at the Bernabéu will be as a substitute or spectator at a season-ending home game, if his recovery holds to schedule. A player who gave the club everything deserves a more fitting farewell.