Women's flyweight Tracy Cortez is expected to step in for Maycee Barber and and face Rose Namajunas in the UFC Denver main event on July 13, sources told MMA Fighting's Mike Heck and Damon Martin.

Barber withdrew from the fight against Namajunas on Tuesday for an undisclosed reason.

Cortez, the 125-pound division's No. 11-ranked contender, is undefeated in the UFC at 5-0. Cortez, who debuted in the promotion in 2019, is coming off a unanimous decision win over Jasmine Jasudavicius last September.

Namajunas, the sixth-ranked fighter at 125 pounds and a former two-time strawweight champ, snapped a two-fight skid with a decision win over Amanda Ribas in a March main event. Namajunas, 31, holds a 1-1 record at women's flyweight.

Barber, the fourth-ranked women's flyweight, was looking to extend her winning streak to seven.

Cortez stepping in for Barber isn't the only recent change to UFC Denver. The welterweight co-main event between Mike Malott and Gilbert Urbina was canceled Wednesday due to an undisclosed injury, sources told Sportsnet's Aaron Bronsteter.