Age: 16
Birthday: April 1
Height: 175 cm (5' 9")
Blood Type: B
Skills: Spatial Awareness, Direct Shot, Adaptability, Flow State, Meta Vision

Yoichi Isagi is the main protagonist of Blue Lock and is among the 300 players picked to compete in the Blue Lock Project.

Previously a second-year football player at Ichinan High and now #299 in Blue Lock. He aspires to become a great hero like Noel Noa. Yoichi plays as a striker and is a team player.

While playing football, Yoichi is great at remaining calm during pressure. He works with his teammates, but is capable of being selfish like a "true striker."

He begins by competing in a high school match and as his team is desperate for a goal, he was found on a break away and 1-on-1 with the opposing goalkeeper in which he decided to pass to his teammate, and his teammate misses that led his team into missing out in the interhigh. He then regrets the play that he did and he then receives an invitation to the upcoming Blue Lock Project. This is the project that will soon change his life forever!