Saul “Canelo” Alvarez successfully defended his World Boxing Council middleweight title in spectacular fashion Saturday with a devastating sixth-round knockout of Amir Khan in Las Vegas.

The 25-year-old Mexican dropped Khan with a straight right hand over a left jab that sent the Briton crumbling to the canvas with just 23 seconds left in the round.

It was a shocking end to what had been a surprisingly close fight up to that point as Khan moved up two weight classes to face the bigger champ.

Alvarez is now mandated by the WBC to fight unbeaten two-belt champ Gennady Golovkin, who was at ringside Saturday.