Injuries to Isaac Vallie-Flagg and Kelvin Tiller have opened the door for Kamuela Kirk and Brian Grinnell to compete this Friday night at World Series of Fighting 23.

Kirk replaces Vallie-Flagg and fights Estevan Payan, while Grinnell steps in for Tiller vs. Vagab Vagabov. Both bouts are part of the online prelim stream ahead of the NBC Sports Network main card.

In the main event, Justin Gaethje defends his lightweight title against Luis Palomino, while David Branch and Teddy Holder battle for the vacant light heavyweight title.

Below is the current lineup:

MAIN CARD (NBC Sports Network/10 p.m. ET)

WSOF Lightweight Championship
Justin Gaethje (c) vs. Luis Palomino

Inaugural WSOF Light Heavyweight Championship
David Branch vs. Teddy Holder

Bantamweight: Timur Valiev vs. Tito Jones

Catchweight: Phoenix Jones vs. Roberto Yong

Lightweight: Brian Foster vs. LaRue Burley

PRELIMINARY CARD (Online/6:45 p.m. ET)

Middleweight: Vagab Vagabov vs. Brian Grinnell

Middleweight: Clifford Starks vs. Krasimir Mladenov

Lightweight: Estevan Payan vs. Kamuela Kirk

Welterweight: Matthew Frincu vs. Danny Davis, Jr.

Bantamweight: Andres Ponce vs. David Nuzzo

Bantamweight: Randy Steinke vs. Joey Miolla

Lightweight: Benny Madrid vs. Jeff Fletcher