The latest chapter in Blue Lock looks to be building up to something totally unpredictable in the story. So far, the top 23 players from the program have been chosen and are being prepared for their next challenge - the U-20 World Cup. With 30 days in hand, they are set to face Nigeria, France, and England (in that order) as Phase 3. However, as can be seen, these 23 players exclude Nagi Seishiro.
Believed to possess extraordinary talent, the boy "withered" away his gifts depending on other players, like Reo and Isagi. True enough, he displayed moments of brilliance and showcased that innate aptitude for football. But he was ultimately ousted from Blue Lock. His case stands as an instance of the program not having any "heroes," and a clear parallel has been made.
Disclaimer: This article reflects the writer's opinions.
Blue Lock: Parallels in the manga show that there are no "heroes"

Through its most recent chapters, Blue Lock used Nagi Seishiro to show that there aren't any "heroes" in the series. Defeated and shown the door, the white-haired boy was made to realize the reality of his situation. He was quite talented, not to be mistaken, but the brand of football he was playing didn't match and wasn't needed in the program.
Moreover, due to their beginnings, he had developed a dependence on Reo Mikage. Reo managed to adapt and evolve after realizing the potential consequences of not doing so. During the selections in the program and particularly during the Neo Egoist League Arc, he reinvented himself. He was able to evolve into a player who could succeed on his own, much like the other players.
However, this wasn't true for Nagi, as he always seemed to depend on someone first, Reo, then Isagi, and then Reo again at Manshine City. In the team's final game, he showcased a moment of brilliance and scored to equalize against FC Barcha. But then again, he couldn't create a pathway to another goal, a game-winning move that would decide his fate. Hence, he was eliminated.

Now, the parallels made in the panels in the manga (chapters 303 and 309) depict that there are no "heroes". Before addressing Nagi, a similar thing happened to Kunigami Rensuke. During the Second Selection, he was eliminated from the program. At the time, his character had dreamed of becoming a "football hero" and making it to the top. But those dreams were shattered in Blue Lock.
However, his road didn't end there as he was given a second chance, i.e., the Wildcard. This involved a massive change in his personality and role as a player. He went from sociable and cool to cold, aggressive, and very driven. This change was so drastic that he ultimately chose to resort to being the "villain" (Neo Egoist League Arc).
Now, in Nagi's case, the mentioned parallels could be a foreshadowing of his return to the program. His time alone presently has allowed him to fully process Blue Lock and what exactly it is that ignites "the fire" in him - football or the program. There is even a villainous game character shown, as well as Buratsuta's tempting offer to him. That is his only way of becoming a professional currently.
Thus, it is possible that Nagi returns to the biggest stage, likely akin to Kunigami, but as a transformed individual. Only time will tell whether it is through Buratsuta's offer or some other means (Gurimu's return).
In conclusion

The most recent story developments have underscored one major theme - there are no "heroes" in this story who evolve or perish. That is what happened to Nagi Seishiro, whose journey ended after the Neo Egoist League. His reliance on players like Reo and Isagi stunted his growth despite him being gifted with talent for the game.
However, Nagi's closest ally, Reo, was able to evolve, reinvent, and earn his place in the U-20 World Cup squad. Looking closely, the manga subtly draws parallels between Kunigami and Nagi - both once promising, cast out, and compelled to face a harsh reality. Kunigami’s transformation into a “villain” teases that Nagi could be headed the same way.
With Buratsuta’s offer on the table, Nagi has one final chance - fade away or become something new. If continued, his journey will be one of reinvention, as he now understands and will chase that "fire" to be the best.
Related links:
- Why Blue Lock sidelined Nagi as Isagi's rival, explained
- Is Blue Lock EPISODE Nagi canon? explained
- Could Sae be on the verge of becoming the next Nagi in Blue Lock? Explored