Rinsagi

Rinsagi is the slash ship between Itoshi Rin and Isagi Yoichi from the Blue Lock fandom.

First Stage
The first time Isagi sees Rin is in Chapter 40 when the Second Selection began. Rin didn't falter like the rest of them and immediately went through the gate after kicking two balls and making them collide with each other in midair, showcasing his skill. Isagi describes Rin's kicks as beautiful and clean, calling him incredible.

After Rin goes through the gate to the Second Selection, the screen above it displays the words "Challenger: Itoshi Rin". Team Z draw parallels to the genius Itoshi Sae from the New Generation's World 11.

Second Stage
After forming a team of three with Bachira and Nagi, Isagi enters the Third Stage with them to find Rin, Aryu, and Tokimitsu waiting for another team to arrive. Isagi recognises Rin immediately and is at first hesitant to battle him, but after learning that not only does the winning team get to steal one of the losing team's members, but Rin is indeed the younger brother of Itoshi Sae, his "ego" urges him to fight Rin.

Isagi is determined to win and steal Rin, but Rin's immense talent overwhelms everyone on the field, even his own teammates. Rin scores a goal with a straight shot from the centre line in the kick off, calling them all lukewarm and a waste of time. This is where their rivalry really begins to stem. Isagi calls Rin lukewarm (aka Rin's catchphrase) for not thinking he'd be able to see the same scenery. In the final moments of the game where the score is 4-2 in Rin's team's favour, Isagi believes can control the field and take back the game, but for the first time Rin approaches and challenges him. Isagi thinks Rin's underestimating him, but Rin, who Isagi then realises is who's really in control, sees right through his plans. Isagi describes their difference in skill incredibly overwhelming and as he helplessly watches Rin advance towards the goal, he says he's completely smitten by the beauty of the parable Rin's kick drew.

Fourth Stage
Isagi finds Rin and Bachira and challenges Rin to a rematch with their new teams: Team White (Isagi, Nagi, Barou, and Chigiri) versus Team Red (Rin, Aryu, Tokimitsu, and Bachira.) Isagi originally plans for him to face off with Rin in the centre, but Nagi ends up asking to face Rin instead. Isagi agrees but says he'll step in to crush Rin if Nagi loses. As the match goes on, Isagi comes to the conclusion that the only one who's able to keep up with Rin's thinking is him, but Rin's thinking is faster than his. Midgame is where Rin starts to get serious and he controls both his teammates and the opposing team like puppets. It all boils down to who can take control of Barou and the field, Isagi or Rin, but Bachira finally awakens and ultimately, Team Red wins. Rin tells his teammates to shut up and chooses Isagi as their fifth and last teammate, saying "I won't let you sink here. Come, Isagi Yoichi. You can have a front row view of my ascension to the world's number one."

Fanon
The Foe Yay involving the two characters it's what made the ship become charming to fans, as the "Enemies to Lovers" trope is very popular and common amongst anime franchises involving the shonen genre.

On AO3, it's the third most popular ship on the fandom (both anime/manga), being the first most written for Rin and the second most for Isagi right behind Bachisagi.

Fandom
FAN FICTION

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PIXIV

WIKI
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