Canelo Alvarez, who is among the three best boxers in the world, will step up for a fresh challenge this weekend when he attempts to win a championship in a higher division.

The 35-year-old Golovkin, making his Las Vegas debut, kept hold of the World Boxing Council, World Boxing Association and International Boxing Federation belts in front of a crowd of 22,358 at the T-Mobile Arena.

Gennady Golovkin says defending his world titles against Canelo Alvarez in his first fight in Las Vegas may be the most difficult bout of his career.

Canelo Alvarez defended his World Boxing Council middleweight belt Saturday by knocking out Amir Khan with a vicious right hand late in the sixth round of their Las Vegas title fight.