British superstar Amir Khan says Terence Crawford's record is very deceiving -- claiming that his 34-0 record is littered with lower level opponents.

In fact, Khan says if he fought the kind of opponents Crawford has beaten, he'd be undefeated as well.

Khan will challenge Crawford for the WBO welterweight world title on April 20 at Madison Square Garden in New York City... in a fight where Khan is widely seen as an overwhelming underdog. The event will be carried by ESPN Pay-Per-View.

Khan says the so-called experts have it all wrong -- because he's faced (and beaten) much better fighters than Crawford has.

"Look at my resume, look at the people I’ve beaten. My resume is a lot better than Terence Crawford's. I've fought better opponents, beaten better opponents. Okay fine, he’s unbeaten, but I’m sure I would be unbeaten if I fought all the guys he did," Khan told TMZ Sports.

Khan has victories over former world champions like Zab Judah, Luis Collazo, Marcos Maidana, Devon Alexander, Chris Algieri, Marco Antonio Barrera and Paulie Malignaggi.

And Amir's losses have come against fighters like Canelo Alvarez, Lamont Peterson, Breidis Prescott and Danny Garcia. Khan has never tasted defeat at the welterweight limit of 147 and believes that his body is best suited for the weight class.

Most observers view Crawford's big victories as coming against Yuriokis Gamboa, Viktor Postol and Jeff Horn.

"[Crawford has] not fought anyone like me," Khan said... "This is his hardest fight on paper in his boxing professional career. That should say it all."

Crawford believes that he's going to take Khan to town when when they meet in the ring. He has this simple advice for gamblers -- "If you wanna lose some money, bet on [Amir Khan]."