A pair of IBF elimination matches will round out Showtime’s tripleheader December 17 in Las Vegas.

BoxingScene.com has learned that the network will televise a 12-round, 168-pound eliminator between Jose Uzcategui and Vladimir Shishkin as its co-feature before unbeaten lightweights Frank Martin and Michel Rivera square off in the main event at The Cosmopolitan of Las Vegas. In the opener of Showtime’s three-bout broadcast, bantamweight contenders Nikolai Potapov and Vincent Astrolabio have agreed to meet in a 12-round, 118-pound eliminator.

Uzcategui is the IBF’s seventh-ranked contender for one of Canelo Alvarez’s four super middleweight titles. The Venezuelan veteran initially thought his fight against WBC interim champion David Benavidez would be rescheduled for some point in January, but Benavidez instead will face rival Caleb Plant, a former IBF champ, at some point in March in a pay-per-view main event.

The 31-year-old Uzcategui (32-4, 27 KOs) has won three bouts by knockout or technical knockout since American Lionel Thompson (22-5, 12 KOs) upset him by 10-round unanimous decision in December 2019 at State Farm Arena in Atlanta. Tijuana’s Uzcategui was supposed to battle Benavidez in a “Showtime Championship Boxing” main event last November 13 at Footprint Center in Phoenix, but he tested positive for recombinant erythropoietin (EPO), which is on the Voluntary Anti-Doping Association’s list of banned substances.

Uzcategui was replaced by Kyrone Davis (16-3-1, 6 KOs), whom Benavidez beat by seventh-round technical knockout.

Shishkin (13-0, 8 KOs), a 31-year-old Russian contender, is ranked ninth by the IBF in the super middleweight division.

Russia’s Potapov (23-2-1, 11 KOs) is the IBF’s third-ranked contender for its bantamweight champ, Japanese star Naoya Inoue (23-0, 20 KOs). Potapov, 32, has won three straight fights since he suffered a controversial 12-round, majority-decision defeat to Chicago’s Joshua Greer Jr. (22-3-2, 12 KOs) in July 2019 at Prudential Center in Newark.

The Philippines’ Astrolabio (17-3, 12 KOs) upset former super bantamweight and bantamweight champion Guillermo Rigondeaux (20-3, 13 KOs) by unanimous decision in their 10-rounder February 26 in Dubai. Astrolabio, 25, is the IBF’s sixth-ranked contender in the bantamweight division.

Indianapolis’ Martin (16-0, 12 KOs) and the Dominican Republic’s Rivera (24-0, 14 KOs) will square off in a WBA lightweight elimination match in the main event.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.