Saturday's Showtime Championship Boxing's tripleheader from The Cosmopolitan of Las Vegas will be headlined by Rolando “Rolly” Romero (139.5 pounds) and Ismael Barroso (139) facing off for the vacant WBA junior welterweight championship... former two-division champion Rances Barthelemy (142.5) duels Omar “El Relámpago” Juarez(142.25)...  junior welterweight contenders Batyr Akhmedov (138.75) and Kenneth Sims Jr. (139.25) meet in a WBA elimination bout.  Prior to the telecast, three match-ups featuring undefeated fighters will highlight the Showtime Boxing Countdown live streaming presentation on the Showtime Sports YouTube channel and Showtime Boxing Facebook page beginning at 6:30 p.m. ET/3:30 p.m. PT. It will be topped by Esteuri “El Puma” Suero (139.2) dueling Starling Castillo (139.6) in a ten-round attraction... Also featured will be bantamweight Michael Angeletti (118.2) in an eight-round bout against Michell Banquez (118.8)... super featherweight Justin Viloria (127.6) will take on Pedro Pinillo (129.2) in a six-round fight.