After a goalless first half, Japan struck twice in seven minutes following the interval to take full control of a gripping last-16 tie in Rostov-on-Don on Monday.
Genki Haraguchi and Takashi Inui scored stunners as Japan looked set to reach the first World Cup quarter-final in their history.
But, instead, Belgium became the first team to come from two goals down to win in a World Cup knockout game since 1970 and will now face five-time winners Brazil on Friday.
Jan Vertonghen’s looping header somehow beat goalkeeper Eiji Kawashima and Belgium’s aerial power started to tell when Marouane Fellaini thumped home Eden Hazard’s brilliant left-wing cross.
Keisuke Honda almost beat Thibaut Courtois with a free-kick in injury time but a clinical Belgium counter-attack, which ended in Thomas Meunier setting up Chadli for a simple finish, broke
MATCH FACTS AND STATS
BELGIUM: (3-4-3) Courtois; Alderweireld, Kompany, Vertonghen; Meunier, De Bruyne, Witsel, Carrasco (Chadli 65); Mertens (Fellaini 65), Lukaku, Hazard
SUBS NOT USED: Casteels (GK), Mignolet (GK); Batshuayi, Boyata, Dembele, Dendoncker, Hazard, Januzaj, Tielemans, Vermaelen
GOALS: Vertonghen (69); Fellaini (74); Chadli (94)
COACH: Roberto Martinez
JAPAN: (4-2-3-1) Kawashima; H. Sakai, Yoshida, Shoji, Nagatomo; Hasebe, Shibasaki (Yamaguchi 81); Haraguchi (Honda 81), Kagawa, Inui; Osako
SUBS NOT USED: Higashiguchi (GK), Nakamura (GK); Endo, Makino, Muto, Okazaki, Oshima, G. Sakai, Ueda, Usami
GOALS: Haraguchi (48); Inui (52)
BOOKINGS: Shibasaki (40)
COACH: Akira Nishino
REFEREE: Malang Diedhiou (Senegal)
VENUE: Rostov Arena.