Sae Itoshi

Sae is a tall, lean young man with reddish-brown/maroon hair and slim teal eyes that are framed by an array of long underlashes just like his brother, Rin. During the National Representative match, he wears the Japan U-20 White #10 jersey with a black shirt underneath the jersey and some black gloves.

Since a young age, Sae has been cold, blunt, and serious. He has only ever cared about becoming the best Midfielder in the world and has only had time for things that get him closer to his goal. Sae can also be arrogant and condescending, looking down on others even if they are older than him and wield organizational authority. He is egotistical in his football play but has shown to be able to restrain himself and play his position, not trying to outshine others unnecessarily.

Sae is prideful as a football player, looking down on Japanese football and all who participate in it. Sae states that he would much rather die or play in Europe with a bunch of college students than play in the J-League or play on the Japan National Team. He is very confident in his skills and wholeheartedly believes that nobody in Japan is worthy of his skills as a teammate. He dislikes the fact that he was born in Japan, saying things like he was simply born in the wrong country.

Though Sae is a difficult person, he is not impossible to work with. He, out of pure interest, decides to stay in Japan on a whim after hearing about the Blue Lock Project and even joins the Japan U-20 for the match against the Blue Lock Eleven. But when his interest is satisfied, he has no problem abandoning those he deems unworthy of his time. Despite Sae's arrogance, he does not mind staying in his role as a midfielder and key passer. During the Japan National Representative match, Sae gave the Japan U-20 forwards every opportunity to score, and only after repeated failures did he decide to score himself. After the game between Japan U-20 and Blue Lock Eleven, Sae is not above admitting when he is wrong, as he tells Rin that he was wrong about Japan; they are capable of creating good strikers and that their football can still change.

During their childhood, Sae is shown to be much friendlier, more caring and loving towards his brother Rin. He even took responsibility for Rin destroying his toys.

Rin Itoshi is his younger brother. They used to be quite close with each other in their childhood. Sae was admired by Rin and he was the reason Rin started to play football. Sae and Rin used to play together and won many games together, they even made a promise to become the two best strikers in the world. However, they got separated when Sae was scouted to play in the inferiors of the Real Madrid. Four years later, Sae and Rin met again while the last one was training late. Sae then tells him that he will become the best midfielder instead of the best striker of the world, the thing that greatly affected Rin since his reason to play football had been his older brother. Sae then challenges Rin to play a one-on-one and tells him that if he defeats him he will retake that dream with Rin. Sae utterly defeats Rin and says he feels disgusted with him and the football of Japan, also telling Rin to never use him as a reason to play football ever again, leaving his younger brother behind while he stays in the field shocked and later at his home swears to destroy Sae.

Later on, their relationship fell apart and estranged, never seeing each other until the match between Japan U-20 and Blue Lock Eleven. Sae is absolutely indifferent to Rin and doesn't speak to him until they have another one-on-one, in which Sae tells him that he will never be able to defeat him as long as he keeps considering himself as "Sae Itoshi's younger brother". And while Rin tries his best to prove that he is better that his brother, Sae doesn't pay him attention. Ultimately, despite Rin successfully besting him in their fight, he still looked down on his brother and instead acknowledged his teammate Isagi, for his talent in achieving goals.

Isagi Yoichi: During the Japanese Representative Match, Sae was surprised to find out that Isagi is the "Heart of Blue Lock". He was impressed by how he was able to plan different ways to score goals, to motivate his fellow teammates, and to inspire them to achieve victory throughout the match. Sae was also amazed on how Isagi managed to manipulate Rin into entering Flow, as well as take advantage of Rin's awakening to secure his defining chance for a victory shot. He even bluntly stated to Rin that Isagi will be the one to change Japanese football for the better, making him the first Japanese striker that he ever truly respected. In the aftermath of Japan's victory over Nigeria in the U-20 World Cup, Sae expressed disappointment that Isagi and the rest of the U-20 team didn't score 8 goals instead of 4 against their mediocre Nigerian opponents.

Oliver Aiku: Like with all members of the original U20 Japanese team, Sae had a very low opinion of Oliver, considering him to be very mediocre in his plays. Yet, he has shown to respect his clever tactical scheme in manipulating both himself and the heads of the Japan Football Union, which led to his endgame of entering Ryusei Shido into the game against Blue Lock Eleven, to prove to the world once and for all that Japanese football's "team-play" philosophy is defective and "egoism" is the key to victory.

Bunny Iglesias: Not much is known about their relationship, but it is shown that Sae has bitter and distasteful feelings towards the forward when he was watching him on TV[1]. This can imply that they had a negative past with each other when Sae played in Spain. Bunny is also the main reason why Sae wants to join the U-20 World Cup[2], insinuating a deep and intense rivalry between the two.

SHIDOU RYUSEI: Their first introduction to each other is when Sae tells Shidou that Blue Lock is too small of a cage for him. He tells Shidou to hand over his ego and go wild for Sae’s sake. Shidou first reacts angrily but is much more intrigued by the end of the scene. During the second half of the match, Shidou is finally subbed in. He and Sae pair up instantly, overwhelming not only the other team but their own teammates as well. A fellow U-20 player, Oliver Aiku even comments on how Shidou and Sae are a match made in heaven.

After an incident with another player, Shidou is rewarded with a free-kick opportunity to score. During this, he and Sae work together to plan the very best route Shidou can take to score his goal. Sae encourages him to think outside of the box and imagine his very best goal rather than the “realistically possible” goal. Shidou quickly comes up with his ideal goal and tells Sae that he says very exciting things. Sae tells him that this is the time to dream and to fall under his spell. Shidou responds by asking if he’s Cinderella now, then says he’s falling in love. Together, Shidou and Sae score the goal. After their goal, Shidou compliments Sae on his assistance. He tells Sae he likes him and asks for his number. Sae says he’ll give it over if Shidou scores a hat trick (a hat trick is when a player scores three goals in a game).

Shidou now looks even more excited than he was before. After a pass from Sae to Shidou, Shidou compares playing football with Sae to the feeling of electricity pulsing through his brain. Sae asks him to elaborate, and he answers by saying that he doesn’t really know, but this is the first time he’s ever felt that his freedom has been understood by someone. Shidou blushes and comments on his excitement again. Sae reminds him that he still needs to score his goal before he gets too excited. After Shidou scores his second goal, his teammates run toward him to congratulate him, but he ignores them and goes to Sae.

Girolan Dabadie: Girolan is Sae's manager as he has to plan all events that Sae gets into as well as respresent him on negotiations. While Sae doesn't seem to care much about him, Girolan shows to be careful with Sae, asking him not to say things that could hurt the press.