Free agent Colin Kaepernick working towards NFL comebackQuarterback Colin Kaepernick conducted a 90-minute private workout in a private practice field on Thursday morning in the Houston area.SI Staff|Share on FacebookShare on XAdd us on Quarterback Colin Kaepernick conducted a 90-minute private workout in a private practice field on Thursday morning in the Houston area.Published Mar 15, 2018SI STAFFShare on FacebookShare on XHome/NFL