WBO welterweight champion Jeff Horn (17-0-1, 11 KOs) is warning everyone not to underestimate him in a potential mandatory defense against Terence Crawford, which may happen in the first half of 2018.

Back in August, Crawford (32-0, 23 KOs) unified the entire junior welterweight division when he stopped Julius Indongo to unify the WBC, WBO, WBA, IBF world titles.

Horn came on the scene in July, when he secured an upset twelve round unanimous decision over Manny Pacquiao to capture the WBO title before a crowd of over 51,000 at Suncorp Stadium in Brisbane.

After a rematch with Pacquiao fell through, Horn finalized a deal to face England's Gary Corcoran in a voluntary defense at the Brisbane Convention and Exhibition Centre on December 13th.

If he beats Corcoran and then take on Crawford, Horn would be tabbed as a serious underdog in the fight.

But Horn cautions, underestimate him at your own risk when he faces Crawford.

"Everyone should learn not to underestimate me. That's one of my biggest strengths; people underestimate me and then I win. Nobody is going to take this belt away from me cheaply," Horn told The Daily Telegraph.

As part of his victory over Pacquiao, Horn obligated to promoter Bob Arum of Top Rank for a few fights. He says the mandatory against Crawford would be the final bout of that deal.

"Bob Arum wants one of his fighters to hold on to that belt. He's got a two-fight deal with me, so Terence Crawford would be my last one. It depends if we are going to renegotiate a contract or whether he wants Terence to win because he's a Top Rank fighter," Horn said.

"I'm not going to look too far ahead. I've got to take care of Gary first. He's told me he wants to take this belt from me so that has to be my focus. Then I'll see who the No.1 contender is next year."