Amanda Serrano, already the only female boxer to win world titles in five weight classes, will go for one in a sixth.
Serrano (34-1-1, 26 KOs), 29, a Puerto Rico native fighting out of Brooklyn, has won world titles at bantamweight, junior featherweight, featherweight, junior lightweight and lightweight.
"I'm super excited to be fighting for a world title in my sixth weight class," Serrano said.
In the boxing ring, Serrano is a record-breaker, becoming the only female boxer to win world titles in five weight classes, and on Sept. 8, she will attempt to break her own record, vying for a sixth division championship.
Reynoso (11-4-3, 8 KOs), 22, of Argentina, has had two previous opportunities to fight for a world title -- at junior welterweight and junior middleweight -- but lost each time.