Amir Khan insists he didn't think twice before accepting a fight against Terence Crawford.
The Brit takes on the three-weight world champion at Madison Square Garden in New York on Saturday night.
Crawford is unbeaten in 34 fights and is considered among the best pound-for-pound fighters in the world.
But Khan is confident he can upset the odds and restore his own standing in the sport.
"A lot of people don't want to fight Terence Crawford," he told BT Sport .
"When the phone call came to me I was like, 'yeah I'll fight him!'"
Khan is settled at welterweight following an ill-advised move to middleweight which saw him brutally knocked out by Canelo Alvarez.
And he added: "We’ve both been hurt but I’m a fully-fledged welterweight who hits hard.
"I'm am unbeaten welterweight fighter and it's the weight I feel comfortable at and that I feel strong at.
"I’ve got the perfect size whereas the other weights might have been too much for me, like when I fought Canelo.
"Crawford is a very skilled fighter and I can’t take him lightly – he’s got power, he’s durable and he moves well.
"For me to win this fight I have to be on my A-game and make no mistakes.
"I'm not going to go in there thinking I’m the bigger fighter, my skills will win me this fight, not my size or my power. My IQ will win this one."