The two Selecao stars missed the last two group-stage matches with ankle injuries, but they have recovered in time for the knockout rounds, with head coach Tite thrusting them both straight back into the first XI.
Tite has made a total of 10 changes to the side that lost 1-0 to Cameroon on Friday, with Real Madrid defender Eder Militao the only player to retain his place.
With captain Thiago Silva and Marquinhos both returning at centre-back, Militao will switch to right-back, while Danilo will operate on the left side of the back four as Juventus teammate Alex Sandro remains out with a hip problem. First-choice goalkeeper Alisson Becker, meanwhile, returns between the sticks at the expense of Ederson.
In midfield, Fred and Fabinho have been replaced by Casemiro and Lucas Paqueta, while Raphinha, Neymar and Vinicius Junior all start in attack along with central striker Richarlison.
As for South Korea, Paulo Bento has made two changes to his starting lineup, with Napoli's Kim Min-jae and Wolverhampton Wanderers' Hwang Hee-chan coming in for Kwon Kyung-won and Lee Kang-in respectively.
Kim Young-gwon earns his 100th international appearance at centre-back alongside Min-jae, while star attacker Son Heung-min is joined in the front three by Hee-chan and Cho Gue-sung.
Brazil starting lineup: Alisson; Militao, Thiago Silva, Marquinhos, Danilo; Casemiro, Paqueta; Raphinha, Neymar, Vinicius Jr; Richarlison
Subs: Weverton, Ederson, Dani Alves, Fabinho, Fred, Guimaraes, Antony, Rodrygo, Ribeiro, Bremer, Pedro, Martinelli
South Korea starting lineup: Seung-gyu; Moon-hwan, Min-jae, Young-gwon, Jin-su; In-beom, Woo-young, Jae-sung; Hee-chan, Gue-sung, Heung-min
Subs: Jong-gyu, Seung-ho, Bum-keun, Jun-ho, Chul, Ui-jo, Sang-ho, Kang-in, Kyung-won, Hyun-woo, Chang-hoon, Tae-hwan, Yu-min, Woo-yeong, Min-kyu