Amir Khan lightened the mood at his final news conference on 4 May, by poking fun at Donald Trump who – just the night before – became the sole Republican candidate for the United States' presidency. Khan who is Muslim and fighting Mexico's Canelo Alvarez took a shot at Trump's immigration pledge.

"You never know, this could be the last fight for me and Canelo here, that's if Donald Trump becomes president. You never know so you have to all tune in come Saturday," Khan joked.

Trump has pledged that, if elected, he would build a wall to keep Mexicans from crossing the US border illegally and put a temporary halt to Muslims entering the US until the threat from "Islamic extremists" can be examined. Khan will challenge Mexico's Saul 'Canelo' Alvarez for his WBC world middleweight title in Las Vegas on 6 May, in what will be the Briton's first fight for a year.

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The 29-year-old Khan, a former Olympic silver medallist and light-welterweight world champion, will be Alvarez's first opponent since the Mexican beat Miguel Cotto in a unanimous points decision in Vegas in November. Alvarez, whose nickname Canelo comes from the Spanish word for cinnamon – owing to his red hair – has only one defeat on an otherwise unblemished record, a majority decision loss to American great Floyd Mayweather. Khan, who boasts a 31-3 record with 19 knockouts, has not fought since outpointing Chris Algieri in New York last May.