The UFC announced that Valerie Letourneau (6-3) had to pull out of her fight with Jessica Andrade (10-3). To replace her, The promotion has signed Larissa Pacheco (10-0) to step in. She is only 19 years old.

UFC Fight Night 51 goes down Sept. 13 at Nilson Nelson Gymnasium in Brasilia, Brazil. The event will air on the UFC Fight Pass. The main event will be Andrei Arlovski vs. Antonio Silva.

The following is the order in which the fights will take place on 9/13:

MAIN CARD - UFC Fight Pass, 8 p.m. ET

Andrei Arlovski vs. Antonio Silva Piotr 

Hallmann vs. Gleison Tibau

Lukasz Sajewski vs. Leonardo Santos 

Wendell Oliveira Marques vs. Santiago Ponzinibbio 

Iuri Alcantara vs. Russell Doane 

Jessica Andrade vs. Larissa Pacheco

PRELIMINARY CARD - UFC Fight Pass, 5:45 p.m. ET 

Dashon Johnson vs. Godofredo Pepey 

Igor Araujo vs. George Sullivan 

Efrain Escudero vs. Francisco Trinaldo 

Sean Spencer vs. Paulo Thiago 

Johnny Bedford vs. Rani Yahya