Rocky Fielding has told ESPN that he believes he can beat Canelo Alvarez at Madison Square Garden on Dec.15.
Fielding (27-1, 15 KOs) is the huge underdog for the fight as he defends the WBA super-middleweight title he won against the previously unbeaten Tyron Zeuge in July.
Mexican superstar Alvarez (50-1-2, 34 KOs) defeated Gennady Golovkin to win the unified middleweight world title in September and has moved up 168 pounds as he attempts to win a title in a third weight division.
But Fielding, 31, says the move up from middleweight will not be easy for Alvarez and is positive he can pull off a famous result at the illustrious New York venue.
"You know at my weight now, at my super middleweight, I'm confident and I believe it," Fielding told ESPN. "I wouldn't take the fight if he asked me to go down to middleweight, obviously it would then be a different story.
"But it's my weight. I'm big, I'm strong and I'm confident I can go in there, upset everyone and shock the world. I wouldn't take it if I didn't believe it. I'm going there as a world champion and I'm going to fight like a world champion and perform like one."
Fielding came face-to-face with Alvarez for the first time at the Empire State Building when the fight was announced in October and immediately noticed the difference in size between them. The Englishman stands at 6'1" and was looking down on the smaller Alvarez, who measures 5'8".
"When we got head to head and [I saw] the height and size that he had I was just boosting more confidence from it," Fielding said.
"I was just getting a good vibe from it. I know how much of a good fighter he is but I'm standing there thinking yeah, if I need to put it on here and have a scrap I'm confident I can use my size and I can do it.
"Then the next day we were back and we were face-to-face every time. It was respectful, I went there being the last one to not look away, he was looking away as we were shaking hands. I enjoyed it and I was trying to let him know that I'm coming here to win and defend my title."