SAN ANTONIO – Members of their camps nearly came to blows after Jermell Charlo and Brian Castano made weight for their 154-pound title unification fight Friday afternoon.

Before they were separated and order was restored at the Thompson San Antonio-Riverwalk hotel, Charlo and Castano both came in below the limit for their 12-round showdown Saturday night at AT&T Center.

Houston’s Charlo, 31, stepped on the Texas Combative Sports Program’s scale at exactly 153 pounds, one below the maximum for their division. Buenos Aires’ Castano, who’s also 31, officially weighed 153¼ pounds.

Charlo-Castano will headline a “Showtime Championship Boxing” tripleheader scheduled to start at 9 p.m. ET.

Barring a draw, the Charlo-Castano winner will become boxing’s first fully unified 154-pound champion during the four-belt era and just the sixth such champion in any division. Retired middleweights Bernard Hopkins and Jermain Taylor, junior welterweights Terence Crawford and Josh Taylor and cruiserweight Oleksandr Usyk are the only boxers who have earned that distinction.

Charlo (34-1, 18 KOs) is listed as more than a 2-1 favorite over Castano (17-0-1, 12 KOs) by most Internet sports books.

Earlier Friday, Anthony Yigit came in a whopping 5.2 pounds overweight for his 12-round, 135-pound title fight against Rolando Romero.

Las Vegas’ Romero weighed in at 135 pounds for what was supposed to be his second defense of the WBA interim lightweight title. Sweden’s Yigit weighed 140.2 pounds for what was scheduled as the first fight of his career at the lightweight limit.

Stockholm’s Yigit (24-1-1, 8 KOs) took what will proceed as a non-title fight on less than two weeks’ notice, despite that he hasn’t fought in more than two years. Yigit replaced Nashville’s Austin Dulay (14-2, 10 KOs, 1 NC), who withdrew from facing Romero (13-0, 11 KOs) due to a knee injury.

The day before Romero’s last fight, Houston’s Justin Pauldo came in almost five pounds overweight. Pauldo (14-1, 7 KOs, 1 NC) was removed from that bout for failing his pre-fight physical by the Mohegan Tribe Department of Athletic Regulation.

Philadelphia’s Avery Sparrow, who was on standby, replaced Pauldo on barely 30 hours’ notice for that January 23 bout. Romero stopped Sparrow in the seventh round at Mohegan Sun Arena in Uncasville, Connecticut.

Before the Romero-Yigit drama Friday, Amilcar Vidal and Immanuwel Aleem met their contractual obligations for the 10-round super middleweight match that’ll open Showtime’s telecast.

Uruguay’s Vidal (12-0, 11 KOs) weighed in at 161½ pounds. Aleem (18-2-2, 11 KOs), of Richmond, Virginia, was slightly heavier, at 162 pounds.

The official weights for the five non-televised fights on the Charlo-Castano undercard are listed below.

Bakhram Murtazaliev (18-0, 14 KOs), Grozny, Russia, 157.2 pounds vs. Khiary Gray (16-5, 12 KOs), Worcester, Masschusetts, 155.8 pounds, 8 rounds, junior middleweights.

Pablo Rubio Jr. (12-0, 4 KOs), Whittier, California, 131.6 pounds vs. Eric Manriquez (7-11-1, 3 KOs, 1 NC), Houston, 131.6 pounds, 6 rounds, lightweights.

Amed Medina (2-0, 2 KOs), Maywood, California, 127.8 pounds vs. Reginald Hinson (1-0), Rock Hill, South Carolina, 128.6 pounds, 4 rounds, junior lightweights.

Roberto Zavala (1-0, 1 KO), Del Rio, Texas, 254 pounds vs. Levi James West (pro debut), Humble, Texas, 199.2 pounds, 4 rounds, heavyweights.

Xavier Nunez (1-0, 1 KO), Corpus Christi, Texas, 129 pounds vs. David Alfaro (1-4), Austin, Texas, 125.4 pounds, 4 rounds, junior lightweights.

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