Saul 'Canelo' Alvarez says he has taken a "risk" in facing Callum Smith but warned he can overcome the champion's significant height and reach advantage.
Alvarez has not lost since 2013 and starts as a favourite against the WBA world super-middleweight champion for Sunday bout.
Photographs of Smith standing seven inches taller than his rival have led some to believe he could land an upset.
Alvarez's only defeat in 56 fights came against Floyd Mayweather.
Promoter Eddie Hearn said the contest is the "fight of the year" and around 12,000 fans will be allowed into the Alamodome to watch it.
The fight program will start at around 1pm on Sunday.
