Manga adaptation of the Kuroko no Basket -Replace- novels, mainly focusing on the Generation of Miracles during their Teikou days.
Summary from BAP Scans
In a certain powerhouse team from Teiko middle school’s basketball club, there was a 5-man group of prodigies called “Generation of Miracles.” And then, there was one more player, highly esteemed by those prodigies, a phantom sixth man – Kuroko Tetsuya. They managed to pull off the outstanding achievement of three consecutive championship wins. Afterwards, a certain incident took place and the team ended up collapsing. This story happens while they’re still in middle-school, before each of them went their separate ways. Episodes featuring Kise and the crew and also the cast from Teiko High-school are included. This is an adaptation for the “Replace” novel series, stepping into the court!