Amir Khan insists he wants to show what he is capable of when he takes on WBC middleweight champion Saul Alvarez.
Khan, who has not been in the ring since beating Chris Algieri in May last year, is full of confidence heading into the fight in Las Vegas on May 7.
Speaking at a press conference in London televised by Sky Sports News HQ, Khan said: "I really promise you're going to see a different Amir Khan in this fight.
"I've been let down so many times in having the biggest fights. There's a lot of big names I've wanted to fight but just couldn't get those fights.
"This is my time now to shine. I want to show the world how good Amir Khan is.
"I'm up against a guy who is a great fighter. Alvarez is a dangerous fighter, he's strong.
"A lot of people are saying to me, 'why do you want to move up to middleweight and fight this huge fighter, this huge puncher?' and I said 'look guys, I really believe I can win this fight'.
"I know I can take his power, take his speed and I really have the tools to win this fight."