Charlo-Castano predictions: Can Jermell Charlo box his way around Brian Castano's pressure?

Jermell Charlo, above, will face Brian Castano with a chance to become junior middleweight undisputed champion. Esther Lin/Showtime

Unified junior middleweight world champion Jermell Charlo is a win away from adding a fourth major title and becoming an undisputed champ. Standing in his way is fellow titleholder Brian Castano, whom he'll face on Saturday at the AT&T Center in San Antonio, Texas (Showtime, 9 p.m. EDT).